485BPOS

As filed with the Securities and Exchange Commission on January 16, 2013

File No. 002-76990
File No. 811-03447

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

POST-EFFECTIVE AMENDMENT NO. 70x

and

REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940

AMENDMENT NO. 72x

SEI TAX EXEMPT TRUST

(Exact Name of Registrant as Specified in Charter)

SEI Investments Company
One Freedom Valley Drive
Oaks, Pennsylvania 19456

(Address of Principal Executive Offices)

(610) 989-1000

Timothy D. Barto
SEI Investments Company
One Freedom Valley Drive
Oaks, Pennsylvania 19456

(Name and Address of Agent for Service)

Copy to:

Timothy W. Levin, Esq.
Morgan, Lewis & Bockius LLP
1701 Market Street
Philadelphia, Pennsylvania 19103

Title of Securities Being Registered. . .Units of Beneficial Interest

It is proposed that this filing will become effective (check appropriate box)

x  immediately upon filing pursuant to paragraph (b)
o  on [date] pursuant to paragraph (b)
o  60 days after filing pursuant to paragraph (a)(1)
o  on [date] pursuant to paragraph (a)(1)
o  75 days after filing pursuant to paragraph (a)(2)
o  on [date] pursuant to paragraph (a)(2) of rule 485.

If appropriate, check the following box:

o  this post-effective amendment designates a new effective date for a previously filed post-effective amendment.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, and the Investment Company Act of 1940, as amended, the Registrant certifies that it meets all of the requirements for effectiveness of this Registration Statement pursuant to Rule 485(b) under the Securities Act of 1933, as amended, and has duly caused this Post-Effective Amendment No. 70 to Registration Statement No. 002-76990 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Oaks, Commonwealth of Pennsylvania on the 16th day of January, 2013.

SEI TAX EXEMPT TRUST
By:	/s/ Robert A. Nesher
Robert A. Nesher
Trustee, President & Chief Executive Officer

Pursuant to the requirements of the Securities Act of 1933, as amended, this Amendment to the Registration Statement has been signed below by the following persons in the capacities and on the date(s) indicated.

*		Trustee	January 16, 2013
Rosemarie B. Greco
*		Trustee	January 16, 2013
William M. Doran
*		Trustee	January 16, 2013
George J. Sullivan, Jr.
*		Trustee	January 16, 2013
Nina Lesavoy
*		Trustee	January 16, 2013
James M. Williams
*		Trustee	January 16, 2013
Mitchell A. Johnson
*		Trustee	January 16, 2013
Hubert L. Harris, Jr.
/s/ Robert A. Nesher		Trustee, President & Chief Executive Officer	January 16, 2013
Robert A. Nesher
/s/ Peter A. Rodriguez		Controller & Chief Financial Officer	January 16, 2013
Peter A. Rodriguez
*By:	/s/ Robert A. Nesher
	Robert A. Nesher
	Attorney-in-Fact

INDEX TO EXHIBITS

EXHIBIT NO.	DESCRIPTION OF EXHIBIT	PAGE NO.
	Risk/return summary of the Funds’ prospectuses as an Interactive Data File using eXtensible Business Reporting Language (“XBRL”)

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET INSTITUTIONAL TAX FREE FUND (First Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	INSTITUTIONAL TAX FREE FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Preserving principal value and maintaining a high degree of liquidity while providing current income exempt from federal income taxes.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Institutional Tax Free Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in municipal money market securities (i) that pay interest that is exempt from federal income taxes and (ii) the interest on which is not a preference item for purposes of the federal alternative minimum tax. The principal issuers of these securities are state and local governments and their agencies located in any of the fifty states, the District of Columbia, Puerto Rico and other U.S. territories and possessions. The Fund uses a sub-adviser (the Sub-Adviser) to manage the Fund's portfolio under the general supervision of SEI Investments Management Corporation, the Fund's adviser (SIMC). The Sub-Adviser seeks to purchase liquid securities with appropriate maturities (i.e., that meet the maturity requirements imposed by Rule 2a-7 under the Investment Company Act of 1940, as amended) that offer competitive yields and that are issued by financially sound issuers. The Sub-Adviser also considers sector allocation and relative valuations in selecting securities for the Fund.    The Fund invests in high quality, short-term debt securities, commonly known as money market instruments. These include municipal bonds, notes, tax-exempt commercial paper and industrial development bonds. The Fund may, to a limited extent, invest in certain taxable securities and repurchase agreements, as well as in securities subject to the alternative minimum tax or in taxable municipal securities. The Fund follows strict Securities and Exchange Commission (SEC) rules about the credit quality, maturity and diversification of its investments.
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Income Risk -- An investment in the Fund is subject to income risk, which is the possibility that the Fund's yield will decline due to falling interest rates. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. A rise in interest rates typically causes a fall in the value of fixed income securities in which the Fund invests, while a fall in interest rates typically causes a rise in the value of such securities. During periods when interest rates are low, the Fund's yield (and total return) also will be low and the income generated by the Fund may not be sufficient to offset all or a significant portion of the Fund's expenses, which could impair the Fund's ability to provide a positive yield and maintain a stable $1.00 share price. Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.    Redemption Risk -- The Fund may experience periods of heavy redemptions that could cause the Fund to liquidate its assets at inopportune times or at a loss or depressed value, particularly during periods of declining or illiquid markets. This could have a significant adverse effect on the Fund's ability to maintain a stable $1.00 share price, and, in extreme circumstances, could cause the Fund to suspend redemptions and liquidate completely. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Although the Fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the Fund.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 0.87% (06/30/07) Worst Quarter: 0.01% (06/30/11) The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012 was 0.02%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	Please call 1-800-DIAL-SEI to obtain the Fund's current yield.
STET INSTITUTIONAL TAX FREE FUND (First Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Management Fees	rr_ManagementFeesOverAssets	0.04%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.65%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.69%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	70
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	221
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	384
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	859
Annual Return 2002	rr_AnnualReturn2002	1.30%
Annual Return 2003	rr_AnnualReturn2003	0.85%
Annual Return 2004	rr_AnnualReturn2004	0.95%
Annual Return 2005	rr_AnnualReturn2005	2.13%
Annual Return 2006	rr_AnnualReturn2006	3.16%
Annual Return 2007	rr_AnnualReturn2007	3.39%
Annual Return 2008	rr_AnnualReturn2008	2.13%
Annual Return 2009	rr_AnnualReturn2009	0.48%
Annual Return 2010	rr_AnnualReturn2010	0.06%
Annual Return 2011	rr_AnnualReturn2011	0.06%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	0.02%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2007
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	0.87%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Jun. 30, 2011
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	0.01%
Label	rr_AverageAnnualReturnLabel	Class A Shares
1 Year	rr_AverageAnnualReturnYear01	0.06%
5 Years	rr_AverageAnnualReturnYear05	1.22%
10 Years	rr_AverageAnnualReturnYear10	1.45%
Since Inception	rr_AverageAnnualReturnSinceInception	3.16%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 03, 1982

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET TAX-ADVANTAGED INCOME FUND (Prospectus Summary) | STET TAX-ADVANTAGED INCOME FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	TAX-ADVANTAGED INCOME FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Provide the highest level of income possible in a tax efficient manner.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	SHAREHOLDER FEES (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 13% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	13.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Tax-Advantaged Income Fund will invest, under normal circumstances, at least 50% of its net assets in municipal securities that pay interest that is exempt from federal income tax, including the alternative minimum tax. The principal issuers of these securities are state and local governments and their agencies located in any of the fifty states, as well as in Puerto Rico and other U.S. territories and possessions. The Fund may invest more than 25% of its total assets in bonds of issuers in California and New York. Under most market conditions, a large percentage of the municipal securities in which the Fund invests will be below investment grade (junk bonds), but the Fund, without limitation, may invest in higher rated municipal securities. To a lesser extent, the Fund will also invest in a full range of preferred stock with an emphasis on preferred securities that, at the time of issuance, are eligible to pay dividends that qualify for certain favorable federal income tax treatment, such as dividends that are treated as qualified dividend income and the dividend received deduction (in each instance, provided certain requirements and holding periods are satisfied, see "Taxes"). Absent further legislation, the favorable federal income tax rates applicable to qualified dividend income will cease to apply in taxable years beginning after December 31, 2012 (for more information, see "Taxes"). The amount invested in preferred stocks at any one time will depend on the attractiveness of the after-tax income stream produced by the preferred securities and will be less than 50% of the Fund's net assets. It is possible that the Fund could own no preferred securities if municipal securities produce a higher yield on an after-tax basis. While a portion of the Fund may invest in securities other than municipal and preferred securities, the Fund will seek to purchase securities that enjoy preferential tax treatment. The Fund may also invest in convertible securities, securities eligible for resale under Rule 144A of the Securities Act of 1933 and other privately placed securities, debt securities subject to federal income tax, common stock and open and closed-end funds. SIMC may directly invest up to 5% of the Fund's assets in closed-end bond funds. The Fund uses a multi-manager approach to manage the Fund's portfolio under the general supervision of SIMC. Each Sub-Adviser and, to the extent applicable, SIMC selects securities based on its view on the future direction of interest rates and the shape of the yield curve, as well as its views on credit quality and sector allocation issues. Where possible, each Sub-Adviser and, to the extent applicable, SIMC, will attempt to acquire securities that are underpriced relative to other eligible securities. Each Sub-Adviser and, to the extent applicable, SIMC, will seek to maintain duration of four to eleven years for the Fund's entire portfolio. The Fund may invest in securities subject to the alternative minimum tax or in taxable debt securities.
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Below Investment Grade Securities Risk -- Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. California/New York Investment Risk -- To the extent the Fund invests a material portion of its assets in issuers of California or New York municipal securities, the Fund's performance will be affected by the fiscal and economic health of the States of California or New York, their political subdivisions, municipalities, agencies and authorities and political and regulatory developments affecting California or New York municipal issuers. Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Convertible and Preferred Securities Risk -- Convertible and preferred securities generally have less potential for gain or loss than common stocks. In addition, convertible and preferred securities generally provide yields higher than the underlying common stocks, but generally lower than comparable non-convertible securities. Because of this higher yield, convertible and preferred securities generally sell at a price above their "conversion value," which is the current market value of the stock to be received upon conversion. The difference between this conversion value and the price of convertible and preferred securities will vary over time depending on changes in the value of the underlying common stocks and interest rates. Convertible and preferred securities are also subject to credit risk and are often lower-quality securities. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Equity Market Risk -- The risk that stock prices will fall over short or extended periods of time. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. Investment Company Risk -- When the Fund invests in an investment company, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the investment company's expenses. In addition, while the risks of owning shares of an investment company generally reflect the risks of owning the underlying investments of the investment company, the Fund may be subject to additional or different risks than if the Fund had invested directly in the underlying investments. Closed-end investment companies issue a fixed number of shares that trade on a stock exchange or over-the-counter at a premium or a discount to their net asset value. As a result, a closed-end fund's share price fluctuates based on what another investor is willing to pay rather than on the market value of the securities in the fund. Liquidity Risk -- The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance. Municipal Securities Risk -- Municipal securities, like other fixed income securities, rise and fall in value in response to economic and market factors, primarily changes in interest rates, and actual or perceived credit quality. Rising interest rates will generally cause municipal securities to decline in value. Longer-term securities respond more sharply to interest rate changes than do shorter-term securities. A municipal security will also lose value if, due to rating downgrades or other factors, there are concerns about the issuer's current or future ability to make principal or interest payments. State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. Non-Diversified Risk -- The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities. Portfolio Turnover Risk -- Due to its investment strategy, the Fund may buy and sell securities frequently. This may result in higher transaction costs and additional capital gains tax liabilities. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. Private Placements Risk -- Investment in privately placed securities may be less liquid than in publicly traded securities. Although these securities may be resold in privately negotiated transactions, the prices realized from these sales could be less than those originally paid by the Fund or less than what may be considered the fair value of such securities. Furthermore, companies whose securities are not publicly traded may not be subject to the disclosure and other investor protection requirements that might be applicable if their securities were publicly traded. Tax Risk -- In order to pay tax-exempt interest, tax-exempt securities must meet certain legal requirements. Failure to meet such requirements may cause the interest received and distributed by the Fund to shareholders to be taxable. Changes or proposed changes in federal tax laws may cause the prices of tax-exempt securities to fall. While the Fund intends, under normal circumstances, to invest at least 50% of its net assets in municipal securities that pay interest that is exempt from federal income tax in order to meet the requirements necessary to pay out exempt-interest dividends to its shareholders, if the Fund fails to meet this requirement, the income from all of its investments, including its municipal securities, may be subject to federal income tax. Loss of money is a risk of investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Loss of money is a risk of investing in the Fund.
Risk Nondiversified Status [Text]	rr_RiskNondiversifiedStatus	The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing the Fund's performance from year to year for the past four calendar years and by showing how the Fund's average annual returns for 1 year, and since the Fund's inception, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing the Fund's performance from year to year for the past four calendar years and by showing how the Fund's average annual returns for 1 year, and since the Fund's inception, compared with those of a broad measure of market performance.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 17.31% (06/30/09) Worst Quarter: -11.47% (09/30/08) The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012 was 13.11%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	reflects no deduction for fees, expenses or taxes
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	This table compares the Fund's average annual total returns to those of a broad-based index and the Fund's 60/40 Blended Benchmark, which consists of the Barclays Capital High Yield Municipal Bond Index and the Barclays Capital Municipal Bond Index. The Fund's Blended Benchmark is designed to reflect a useful comparison to the Fund's overall performance and reflects the Fund's investment strategy more accurately than the broad-based index. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
STET TAX-ADVANTAGED INCOME FUND (Prospectus Summary) | STET TAX-ADVANTAGED INCOME FUND | Barclays Capital High Yield Municipal Bond Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Barclays Capital High Yield Municipal Bond Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	9.25%
Since Inception	rr_AverageAnnualReturnSinceInception	2.43%	[1]
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 04, 2007	[1]
STET TAX-ADVANTAGED INCOME FUND (Prospectus Summary) | STET TAX-ADVANTAGED INCOME FUND | The Fund's 60/40 Blended Benchmark Return
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	The Fund's 60/40 Blended Benchmark Return (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	9.83%
Since Inception	rr_AverageAnnualReturnSinceInception	3.81%	[1]
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 04, 2007	[1]
STET TAX-ADVANTAGED INCOME FUND (Prospectus Summary) | STET TAX-ADVANTAGED INCOME FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	rr_RedemptionFeeOverRedemption	(0.50%)
Management Fees	rr_ManagementFeesOverAssets	0.50%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.64%
Acquired Fund Fees and Expenses (AFFE)	rr_AcquiredFundFeesAndExpensesOverAssets	0.01%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.15%	[2]
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	117
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	365
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	633
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,398
Annual Return 2008	rr_AnnualReturn2008	(19.91%)
Annual Return 2009	rr_AnnualReturn2009	34.13%
Annual Return 2010	rr_AnnualReturn2010	5.25%
Annual Return 2011	rr_AnnualReturn2011	5.70%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	13.11%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	17.31%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Sep. 30, 2008
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(11.47%)
Label	rr_AverageAnnualReturnLabel	Class A Shares Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	5.70%
Since Inception	rr_AverageAnnualReturnSinceInception	3.26%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 04, 2007
STET TAX-ADVANTAGED INCOME FUND (Prospectus Summary) | STET TAX-ADVANTAGED INCOME FUND | CLASS A | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	5.03%
Since Inception	rr_AverageAnnualReturnSinceInception	2.48%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 04, 2007
STET TAX-ADVANTAGED INCOME FUND (Prospectus Summary) | STET TAX-ADVANTAGED INCOME FUND | CLASS A | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares
1 Year	rr_AverageAnnualReturnYear01	4.76%
Since Inception	rr_AverageAnnualReturnSinceInception	2.71%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 04, 2007

[1] Index returns are shown from September 30, 2007.

[2] Because the Fund incurred AFFE during the most recent fiscal year, the operating expenses in this fee table will not correlate to the expense ratio in the Fund's financial statements (or the "Financial Highlights" section in the prospectus) because the financial statements include only the direct operating expenses incurred by the Fund, not the indirect costs of investing in other investment companies.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET INSTITUTIONAL TAX FREE FUND (Second Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	INSTITUTIONAL TAX FREE FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Preserving principal value and maintaining a high degree of liquidity while providing current income exempt from federal income taxes.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Institutional Tax Free Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in municipal money market securities (i) that pay interest that is exempt from federal income taxes and (ii) the interest on which is not a preference item for purposes of the federal alternative minimum tax. The principal issuers of these securities are state and local governments and their agencies located in any of the fifty states, the District of Columbia, Puerto Rico and other U.S. territories and possessions. The Fund uses a sub-adviser (the Sub-Adviser) to manage the Fund's portfolio under the general supervision of SEI Investments Management Corporation, the Fund's adviser (SIMC). The Sub-Adviser seeks to purchase liquid securities with appropriate maturities (i.e., that meet the maturity requirements imposed by Rule 2a-7 under the Investment Company Act of 1940, as amended) that offer competitive yields and that are issued by financially sound issuers. The Sub-Adviser also considers sector allocation and relative valuations in selecting securities for the Fund.    The Fund invests in high quality, short-term debt securities, commonly known as money market instruments. These include municipal bonds, notes, tax-exempt commercial paper and industrial development bonds. The Fund may, to a limited extent, invest in certain taxable securities and repurchase agreements, as well as in securities subject to the alternative minimum tax or in taxable municipal securities. The Fund follows strict Securities and Exchange Commission (SEC) rules about the credit quality, maturity and diversification of its investments.
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Income Risk -- An investment in the Fund is subject to income risk, which is the possibility that the Fund's yield will decline due to falling interest rates. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. A rise in interest rates typically causes a fall in the value of fixed income securities in which the Fund invests, while a fall in interest rates typically causes a rise in the value of such securities. During periods when interest rates are low, the Fund's yield (and total return) also will be low and the income generated by the Fund may not be sufficient to offset all or a significant portion of the Fund's expenses, which could impair the Fund's ability to provide a positive yield and maintain a stable $1.00 share price. Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund.    Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. Redemption Risk -- The Fund may experience periods of heavy redemptions that could cause the Fund to liquidate its assets at inopportune times or at a loss or depressed value, particularly during periods of declining or illiquid markets. This could have a significant adverse effect on the Fund's ability to maintain a stable $1.00 share price, and, in extreme circumstances, could cause the Fund to suspend redemptions and liquidate completely. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Although the Fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the Fund.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 0.79% (06/30/07) Worst Quarter: 0.01% (03/31/10) The Fund's Class B total return (pre-tax) from January 1, 2012 to September 30, 2012 was 0.01%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	Please call 1-800-DIAL-SEI to obtain the Fund's current yield.
STET INSTITUTIONAL TAX FREE FUND (Second Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND | CLASS B
Risk Return [Abstract]	rr_RiskReturnAbstract
Management Fees	rr_ManagementFeesOverAssets	0.04%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.70%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.74%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	76
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	237
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	411
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	918
Annual Return 2002	rr_AnnualReturn2002	1.00%
Annual Return 2003	rr_AnnualReturn2003	0.55%
Annual Return 2004	rr_AnnualReturn2004	0.65%
Annual Return 2005	rr_AnnualReturn2005	1.83%
Annual Return 2006	rr_AnnualReturn2006	2.86%
Annual Return 2007	rr_AnnualReturn2007	3.09%
Annual Return 2008	rr_AnnualReturn2008	1.82%
Annual Return 2009	rr_AnnualReturn2009	0.29%
Annual Return 2010	rr_AnnualReturn2010	0.06%
Annual Return 2011	rr_AnnualReturn2011	0.05%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class B total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	0.01%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2007
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	0.79%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2010
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	0.01%
Label	rr_AverageAnnualReturnLabel	Class B Shares
1 Year	rr_AverageAnnualReturnYear01	0.05%
5 Years	rr_AverageAnnualReturnYear05	1.06%
10 Years	rr_AverageAnnualReturnYear10	1.21%
Since Inception	rr_AverageAnnualReturnSinceInception	2.20%
Inception Date	rr_AverageAnnualReturnInceptionDate	Oct. 15, 1990

XML

STET INSTITUTIONAL TAX FREE FUND (Third Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND

INSTITUTIONAL TAX FREE FUND

Investment Goal

Preserving principal value and maintaining a high degree of liquidity while
providing current income exempt from federal income taxes.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold
Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET INSTITUTIONAL TAX FREE FUND CLASS C
Management Fees	0.04%
Distribution (12b-1) Fees	none
Other Expenses	0.90%
Total Annual Fund Operating Expenses	0.94%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET INSTITUTIONAL TAX FREE FUND CLASS C	96	300	520	1,155

Principal Investment Strategies

The Institutional Tax Free Fund will invest, under normal circumstances, at
least 80% of its net assets (plus the amount of any borrowings for investment
purposes) in municipal money market securities (i) that pay interest that is
exempt from federal income taxes and (ii) the interest on which is not a
preference item for purposes of the federal alternative minimum tax. The
principal issuers of these securities are state and local governments and their
agencies located in any of the fifty states, the District of Columbia, Puerto
Rico and other U.S. territories and possessions.

The Fund uses a sub-adviser (the Sub-Adviser) to manage the Fund's portfolio
under the general supervision of SEI Investments Management Corporation, the
Fund's adviser (SIMC). The Sub-Adviser seeks to purchase liquid securities with
appropriate maturities (i.e., that meet the maturity requirements imposed by
Rule 2a-7 under the Investment Company Act of 1940, as amended) that offer
competitive yields and that are issued by financially sound issuers. The
Sub-Adviser also considers sector allocation and relative valuations in
selecting securities for the Fund.
  
The Fund invests in high quality, short-term debt securities, commonly known as
money market instruments. These include municipal bonds, notes, tax-exempt
commercial paper and industrial development bonds. The Fund may, to a limited
extent, invest in certain taxable securities and repurchase agreements, as well
as in securities subject to the alternative minimum tax or in taxable municipal
securities. The Fund follows strict Securities and Exchange Commission (SEC)
rules about the credit quality, maturity and diversification of its investments.

Principal Risks

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced
to reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk -- The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well
as to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Income Risk -- An investment in the Fund is subject to income risk, which is the
possibility that the Fund's yield will decline due to falling interest rates.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates. A rise in interest rates typically causes a
fall in the value of fixed income securities in which the Fund invests, while a
fall in interest rates typically causes a rise in the value of such securities.
During periods when interest rates are low, the Fund's yield (and total return)
also will be low and the income generated by the Fund may not be sufficient to
offset all or a significant portion of the Fund's expenses, which could impair
the Fund's ability to provide a positive yield and maintain a stable $1.00 share
price.

Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities,
to pay interest and principal on municipal debt. Poor statewide or local
economic results or changing political sentiments may reduce tax revenues and
increase the expenses of municipal issuers, making it more difficult for them
to meet their obligations. Actual or perceived erosion of the creditworthiness
of municipal issuers may reduce the value of the Fund's holdings. As a result,
the Fund will be more susceptible to factors that adversely affect issuers of
municipal obligations than a mutual fund that does not have as great a
concentration in municipal obligations. Also, there may be economic or political
changes that impact the ability of issuers of municipal securities to repay
principal and to make interest payments on securities owned by the Fund. Any
changes in the financial condition of municipal issuers may also adversely
affect the value of the Fund's securities.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.

Redemption Risk -- The Fund may experience periods of heavy redemptions that
could cause the Fund to liquidate its assets at inopportune times or at a loss
or depressed value, particularly during periods of declining or illiquid
markets. This could have a significant adverse effect on the Fund's ability to
maintain a stable $1.00 share price, and, in extreme circumstances, could cause
the Fund to suspend redemptions and liquidate completely.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax,
including the federal alternative minimum tax.

An investment in the Fund is not insured or guaranteed by the Federal Deposit
Insurance Corporation (FDIC) or any other government agency. Although the Fund
seeks to preserve the value of your investment at $1.00 per share, it is
possible to lose money by investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance
from year to year for the past ten calendar years and by showing the Fund's
average annual returns for 1, 5 and 10 years, and since the Fund's inception.
The Fund's past performance (before and after taxes) is not necessarily an
indication of how the Fund will perform in the future. For current performance
information, please call 1-800-DIAL-SEI.

Best Quarter: 0.74% (09/30/07)

Worst Quarter: 0.01% (03/31/10)

The Fund's Class C total return (pre-tax) from January 1, 2012
to September 30, 2012 was 0.01%.

Average Annual Total Returns (for the periods ended December 31, 2011)

Average Annual Total Returns	Label	1 Year	5 Years	10 Years	Since Inception	Inception Date
STET INSTITUTIONAL TAX FREE FUND CLASS C	Class C Shares	0.05%	0.95%	1.06%	1.75%	Sep. 11, 1995

Please call 1-800-DIAL-SEI to obtain the Fund's current yield.

XML

STET INSTITUTIONAL TAX FREE FUND (Second Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND

INSTITUTIONAL TAX FREE FUND

Investment Goal

Preserving principal value and maintaining a high degree of liquidity
while providing current income exempt from federal income taxes.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold
Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET INSTITUTIONAL TAX FREE FUND CLASS B
Management Fees	0.04%
Distribution (12b-1) Fees	none
Other Expenses	0.70%
Total Annual Fund Operating Expenses	0.74%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET INSTITUTIONAL TAX FREE FUND CLASS B	76	237	411	918

Principal Investment Strategies

The Institutional Tax Free Fund will invest, under normal circumstances, at
least 80% of its net assets (plus the amount of any borrowings for investment
purposes) in municipal money market securities (i) that pay interest that is
exempt from federal income taxes and (ii) the interest on which is not a
preference item for purposes of the federal alternative minimum tax. The
principal issuers of these securities are state and local governments and their
agencies located in any of the fifty states, the District of Columbia, Puerto
Rico and other U.S. territories and possessions.

The Fund uses a sub-adviser (the Sub-Adviser) to manage the Fund's portfolio
under the general supervision of SEI Investments Management Corporation, the
Fund's adviser (SIMC). The Sub-Adviser seeks to purchase liquid securities
with appropriate maturities (i.e., that meet the maturity requirements imposed
by Rule 2a-7 under the Investment Company Act of 1940, as amended) that offer
competitive yields and that are issued by financially sound issuers. The
Sub-Adviser also considers sector allocation and relative valuations in
selecting securities for the Fund.
  
The Fund invests in high quality, short-term debt securities, commonly known
as money market instruments. These include municipal bonds, notes, tax-exempt
commercial paper and industrial development bonds. The Fund may, to a limited
extent, invest in certain taxable securities and repurchase agreements, as well
as in securities subject to the alternative minimum tax or in taxable municipal
securities. The Fund follows strict Securities and Exchange Commission (SEC)
rules about the credit quality, maturity and diversification of its investments.

Principal Risks

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced
to reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk -- The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well
as to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Income Risk -- An investment in the Fund is subject to income risk, which is the
possibility that the Fund's yield will decline due to falling interest rates.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates. A rise in interest rates typically causes a
fall in the value of fixed income securities in which the Fund invests, while a
fall in interest rates typically causes a rise in the value of such securities.
During periods when interest rates are low, the Fund's yield (and total return)
also will be low and the income generated by the Fund may not be sufficient to
offset all or a significant portion of the Fund's expenses, which could impair
the Fund's ability to provide a positive yield and maintain a stable $1.00 share
price.

Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities,
to pay interest and principal on municipal debt. Poor statewide or local
economic results or changing political sentiments may reduce tax revenues and
increase the expenses of municipal issuers, making it more difficult for them
to meet their obligations. Actual or perceived erosion of the creditworthiness
of municipal issuers may reduce the value of the Fund's holdings. As a result,
the Fund will be more susceptible to factors that adversely affect issuers of
municipal obligations than a mutual fund that does not have as great a
concentration in municipal obligations. Also, there may be economic or political
changes that impact the ability of issuers of municipal securities to repay
principal and to make interest payments on securities owned by the Fund.
  
Any changes in the financial condition of municipal issuers may also adversely
affect the value of the Fund's securities.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.

Redemption Risk -- The Fund may experience periods of heavy redemptions that
could cause the Fund to liquidate its assets at inopportune times or at a loss
or depressed value, particularly during periods of declining or illiquid
markets. This could have a significant adverse effect on the Fund's ability to
maintain a stable $1.00 share price, and, in extreme circumstances, could cause
the Fund to suspend redemptions and liquidate completely.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax,
including the federal alternative minimum tax.

An investment in the Fund is not insured or guaranteed by the Federal Deposit
Insurance Corporation (FDIC) or any other government agency. Although the Fund
seeks to preserve the value of your investment at $1.00 per share, it is
possible to lose money by investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance
from year to year for the past ten calendar years and by showing the Fund's
average annual returns for 1, 5 and 10 years, and since the Fund's inception.
The Fund's past performance (before and after taxes) is not necessarily an
indication of how the Fund will perform in the future. For current performance
information, please call 1-800-DIAL-SEI.

Best Quarter: 0.79% (06/30/07)

Worst Quarter: 0.01% (03/31/10)

The Fund's Class B total return (pre-tax) from January 1, 2012
to September 30, 2012 was 0.01%.

Average Annual Total Returns (for the periods ended December 31, 2011)

Average Annual Total Returns	Label	1 Year	5 Years	10 Years	Since Inception	Inception Date
STET INSTITUTIONAL TAX FREE FUND CLASS B	Class B Shares	0.05%	1.06%	1.21%	2.20%	Oct. 15, 1990

Please call 1-800-DIAL-SEI to obtain the Fund's current yield.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET PENNSYLVANIA MUNICIPAL BOND FUND (First Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	PENNSYLVANIA MUNICIPAL BOND FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Current income exempt from federal and Pennsylvania state income taxes consistent with the preservation of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	SHAREHOLDER FEES (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 12% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	12.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Pennsylvania Municipal Bond Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in investment grade municipal securities that pay interest that is exempt from federal and Pennsylvania state income taxes. The principal issuers of these securities are state and local governments and their agencies located in Pennsylvania, as well as in Puerto Rico and other U.S. territories and possessions. The Fund uses a Sub-Adviser to manage the Fund's portfolio under the general supervision of SIMC. The Sub-Adviser selects securities based on its view on the future direction of interest rates and the shape of the yield curve, as well as its views on credit quality and sector allocation issues. Where possible, the Sub-Adviser will attempt to acquire securities that are underpriced relative to other eligible securities. The Sub-Adviser will strive to maintain an average weighted portfolio maturity of seven years or less. The Fund may, to a limited extent, invest in securities subject to the alternative minimum tax or in debt securities subject to federal and Pennsylvania state income taxes. The Fund may also invest in municipal securities rated below investment grade (junk bonds).
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Below Investment Grade Securities Risk -- Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. Liquidity Risk -- The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.    Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. Pennsylvania Investment Risk -- The Fund's performance will be affected by the fiscal and economic health of the Commonwealth of Pennsylvania, its political subdivisions, municipalities, agencies and authorities and political and regulatory developments affecting Pennsylvania municipal issuers. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. Loss of money is a risk of investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Loss of money is a risk of investing in the Fund.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 5.17% (09/30/09) Worst Quarter: -3.14% (12/31/10) The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012 was 3.62%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	reflects no deduction for fees, expenses or taxes
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
STET PENNSYLVANIA MUNICIPAL BOND FUND (First Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND | Barclays Capital MF Pennsylvania Intermediate Municipal Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Barclays Capital MF Pennsylvania Intermediate Municipal Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	10.18%
5 Years	rr_AverageAnnualReturnYear05	6.21%
10 Years	rr_AverageAnnualReturnYear10	5.52%
Since Inception	rr_AverageAnnualReturnSinceInception	5.31%	[1]
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 26, 1998	[1]
STET PENNSYLVANIA MUNICIPAL BOND FUND (First Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	rr_RedemptionFeeOverRedemption	(0.50%)
Management Fees	rr_ManagementFeesOverAssets	0.35%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.49%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.84%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	86
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	268
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	466
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,037
Annual Return 2002	rr_AnnualReturn2002	9.69%
Annual Return 2003	rr_AnnualReturn2003	4.74%
Annual Return 2004	rr_AnnualReturn2004	2.45%
Annual Return 2005	rr_AnnualReturn2005	2.01%
Annual Return 2006	rr_AnnualReturn2006	3.67%
Annual Return 2007	rr_AnnualReturn2007	3.51%
Annual Return 2008	rr_AnnualReturn2008	(1.52%)
Annual Return 2009	rr_AnnualReturn2009	8.03%
Annual Return 2010	rr_AnnualReturn2010	3.14%
Annual Return 2011	rr_AnnualReturn2011	9.81%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	3.62%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	5.17%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2010
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(3.14%)
Label	rr_AverageAnnualReturnLabel	Class A Shares Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	9.81%
5 Years	rr_AverageAnnualReturnYear05	4.52%
10 Years	rr_AverageAnnualReturnYear10	4.50%
Since Inception	rr_AverageAnnualReturnSinceInception	4.44%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 26, 1998
STET PENNSYLVANIA MUNICIPAL BOND FUND (First Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND | CLASS A | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	9.81%
5 Years	rr_AverageAnnualReturnYear05	4.51%
10 Years	rr_AverageAnnualReturnYear10	4.46%
Since Inception	rr_AverageAnnualReturnSinceInception	4.40%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 26, 1998
STET PENNSYLVANIA MUNICIPAL BOND FUND (First Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND | CLASS A | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares
1 Year	rr_AverageAnnualReturnYear01	7.50%
5 Years	rr_AverageAnnualReturnYear05	4.38%
10 Years	rr_AverageAnnualReturnYear10	4.40%
Since Inception	rr_AverageAnnualReturnSinceInception	4.37%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 26, 1998

[1] Index returns are shown from August 31, 1998.

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STET NEW YORK MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW YORK MUNICIPAL BOND FUND

NEW YORK MUNICIPAL BOND FUND

Investment Goal

The highest level of current income exempt from federal and New York state
and city income taxes as is consistent with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold
Fund shares.

SHAREHOLDER FEES (fees paid directly from your investment)

Shareholder Fees	STET NEW YORK MUNICIPAL BOND FUND CLASS A
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	0.50%

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET NEW YORK MUNICIPAL BOND FUND CLASS A
Management Fees	0.33%
Distribution (12b-1) Fees	none
Other Expenses	0.54%
Total Annual Fund Operating Expenses	0.87%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET NEW YORK MUNICIPAL BOND FUND CLASS A	89	278	482	1,073

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells
securities (or "turns over" its portfolio). A higher portfolio turnover rate
may indicate higher transaction costs and may result in higher taxes when Fund
shares are held in a taxable account. These costs, which are not reflected in
annual Fund operating expenses or in the Example, affect the Fund's performance.
During the most recent fiscal year, the Fund's portfolio turnover rate was 17%
of the average value of its portfolio.

Principal Investment Strategies

The New York Municipal Bond Fund will invest, under normal circumstances, at
least 80% of its net assets (plus the amount of any borrowings for investment
purposes) in investment grade municipal securities that pay interest that is
exempt from federal and New York state and city income taxes. The principal
issuers of these securities are state and local governments and their agencies
located in New York, as well as in Puerto Rico and other U.S. territories and
possessions.

The Fund uses a Sub-Adviser to manage the Fund's portfolio under the general
supervision of SIMC. The Sub-Adviser selects securities based on its view on the
future direction of interest rates and the shape of the yield curve, as well as
its views on credit quality and sector allocation issues. Where possible, the
Sub-Adviser will attempt to acquire securities that are underpriced relative to
other eligible securities. The Sub-Adviser will strive to maintain an average
weighted portfolio maturity of three to ten years. The Fund may, to a limited
extent, invest in securities subject to the alternative minimum tax or in debt
securities subject to federal and New York state and city income taxes. The Fund
may also invest in municipal securities rated below investment grade (junk bonds).

Principal Risks

Below Investment Grade Securities Risk -- Fixed income securities rated below
investment grade (junk bonds) involve greater risks of default or downgrade and
are more volatile than investment grade securities because the prospect for
repayment of principal and interest of many of these securities is speculative.

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced to
reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk -- The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well
as to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates.

Liquidity Risk -- The risk that certain securities may be difficult or impossible
to sell at the time and the price that the Fund would like. The Fund may have to
lower the price, sell other securities instead or forego an investment
opportunity, any of which could have a negative effect on Fund management or
performance.

Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities,
to pay interest and principal on municipal debt. Poor statewide or local
economic results or changing political sentiments may reduce tax revenues and
increase the expenses of municipal issuers, making it more difficult for them
to meet their obligations. Actual or perceived erosion of the creditworthiness
of municipal issuers may reduce the value of the Fund's holdings. As a result,
the Fund will be more susceptible to factors that adversely affect issuers of
municipal obligations than a mutual fund that does not have as great a
concentration in municipal obligations. Also, there may be economic or political
changes that impact the ability of issuers of municipal securities to repay
principal and to make interest payments on securities owned by the Fund. Any
changes in the financial condition of municipal issuers may also adversely
affect the value of the Fund's securities.

New York Investment Risk -- The Fund's performance will be affected by the fiscal
and economic health of the State of New York, its political subdivisions,
municipalities, agencies and authorities and political and regulatory
developments affecting New York municipal issuers.

Non-Diversified Risk -- The Fund is non-diversified, which means that it may
invest in the securities of relatively few issuers. As a result, the Fund may be
more susceptible to a single adverse economic or political occurrence affecting
one or more of these issuers and may experience increased volatility due to its
investments in those securities.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax,
including the federal alternative minimum tax.

Loss of money is a risk of investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance from
year to year for the past ten calendar years and by showing how the Fund's
average annual returns for 1, 5 and 10 years, and since the Fund's inception,
compared with those of a broad measure of market performance. The Fund's past
performance (before and after taxes) is not necessarily an indication of how the
Fund will perform in the future. For current performance information, please
call 1-800-DIAL-SEI.

Best Quarter: 5.32% (09/30/09)

Worst Quarter: -2.86% (12/31/10)

The Fund's Class A total return (pre-tax) from January 1, 2012
to September 30, 2012 was 3.20%.

Average Annual Total Returns (for the periods ended December 31, 2011)

After-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local
taxes. Your actual after-tax returns will depend on your tax situation and may
differ from those shown. After-tax returns shown are not relevant to investors
who hold their Fund shares through tax-deferred arrangements, such as 401(k)
plans or individual retirement accounts.

Average Annual Total Returns STET NEW YORK MUNICIPAL BOND FUND	Label	1 Year	5 Years	10 Years	Since Inception		Inception Date
CLASS A	Class A Shares Return Before Taxes	7.96%	5.00%	4.65%	4.60%		Aug. 18, 1998
CLASS A After Taxes on Distributions	Class A Shares Return After Taxes on Distributions	7.80%	4.93%	4.56%	4.52%		Aug. 18, 1998
CLASS A After Taxes on Distributions and Sales	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares	6.41%	4.75%	4.46%	4.44%		Aug. 18, 1998
Barclays Capital MF New York Intermediate Municipal Index	Barclays Capital MF New York Intermediate Municipal Index (reflects no deduction for fees, expenses or taxes)	9.77%	6.20%	5.56%	5.38%	[1]	Aug. 18, 1998	[1]

[1] Index returns are shown from August 31, 1998.

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STET SHORT DURATION MUNICIPAL FUND (Prospectus Summary) | STET SHORT DURATION MUNICIPAL FUND

SHORT DURATION MUNICIPAL FUND

Investment Goal

High level of income exempt from federal income tax consistent with the
preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold
Fund shares.

SHAREHOLDER FEES (fees paid directly from your investment)

Shareholder Fees	STET SHORT DURATION MUNICIPAL FUND CLASS A
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $25 million within any thirty (30) day period)	0.50%

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET SHORT DURATION MUNICIPAL FUND CLASS A
Management Fees	0.33%
Distribution (12b-1) Fees	none
Other Expenses	0.53%
Total Annual Fund Operating Expenses	0.86%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET SHORT DURATION MUNICIPAL FUND CLASS A	88	274	477	1,061

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells
securities (or "turns over" its portfolio). A higher portfolio turnover rate
may indicate higher transaction costs and may result in higher taxes when Fund
shares are held in a taxable account. These costs, which are not reflected in
annual Fund operating expenses or in the Example, affect the Fund's performance.
During the most recent fiscal year, the Fund's portfolio turnover rate was 42%
of the average value of its portfolio.

Principal Investment Strategies

The Short Duration Municipal Fund will invest, under normal circumstances, at
least 80% of its net assets (plus the amount of any borrowings for investment
purposes) in investment grade municipal securities that pay interest that is
exempt from federal income tax. The principal issuers of these securities are
state and local governments and their agencies located in any of the fifty
states, the District of Columbia, Puerto Rico and other U.S. territories and
possessions. Duration is a weighted average term-to-maturity of the security's
cash flow. The weights are the present values of each cash flow as a percentage
of the present value of all cash flows (i.e., the weights are the present value
of each cash flow as a percentage of the bond's full price).

The Fund uses one or more Sub-Advisers to manage the Fund's portfolio under the
general supervision of SIMC. The Sub-Adviser selects securities based on its
view on the future direction of interest rates and the shape of the yield curve,
as well as its views on credit quality and sector allocation issues. Where
possible, the Sub-Adviser will attempt to acquire securities that are underpriced
relative to other eligible securities. The Sub-Adviser will strive to maintain a
portfolio duration of three years or less. The Fund may, to a limited extent,
invest in securities subject to the alternative minimum tax or in debt securities
subject to federal income tax.

Principal Risks

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced to
reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk -- The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well as
to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates.

Liquidity Risk -- The risk that certain securities may be difficult or impossible
to sell at the time and the price that the Fund would like. The Fund may have to
lower the price, sell other securities instead or forego an investment opportunity,
any of which could have a negative effect on Fund management or performance.

Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities,
to pay interest and principal on municipal debt. Poor statewide or local economic
results or changing political sentiments may reduce tax revenues and increase the
expenses of municipal issuers, making it more difficult for them to meet their
obligations. Actual or perceived erosion of the creditworthiness of municipal
issuers may reduce the value of the Fund's holdings. As a result, the Fund will be
more susceptible to factors that adversely affect issuers of municipal obligations
than a mutual fund that does not have as great a concentration in municipal
obligations. Also, there may be economic or political changes that impact the ability
of issuers of municipal securities to repay principal and to make interest payments
on securities owned by the Fund. Any changes in the financial condition of municipal
issuers may also adversely affect the value of the Fund's securities.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax,
including the federal alternative minimum tax.

Loss of money is a risk of investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance from
year to year for the past eight calendar years and by showing how the Fund's
average annual returns for 1 and 5 years, and since the Fund's inception,
compared with those of a broad measure of market performance. The Fund's past
performance (before and after taxes) is not necessarily an indication of how the
Fund will perform in the future. For current performance information, please
call 1-800-DIAL-SEI.

Best Quarter: 1.51% (12/31/08)

Worst Quarter: -0.26% (06/30/04)

The Fund's Class A total return (pre-tax) from January 1, 2012
to September 30, 2012 was 0.79%.

Average Annual Total Returns (for the periods ended December 31, 2011)

After-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local
taxes. Your actual after-tax returns will depend on your tax situation and may
differ from those shown. After-tax returns shown are not relevant to investors
who hold their Fund shares through tax-deferred arrangements, such as 401(k)
plans or individual retirement accounts.

Average Annual Total Returns STET SHORT DURATION MUNICIPAL FUND	Label	1 Year	5 Years	Since Inception		Inception Date
CLASS A	Class A Shares Return Before Taxes	1.52%	2.66%	2.28%		Nov. 13, 2003
CLASS A After Taxes on Distributions	Class A Shares Return After Taxes on Distributions	1.51%	2.64%	2.26%		Nov. 13, 2003
CLASS A After Taxes on Distributions and Sales	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares	1.44%	2.60%	2.25%		Nov. 13, 2003
Barclays Capital 1-Year Municipal Bond Index	Barclays Capital 1-Year Municipal Bond Index (reflects no deduction for fees, expenses or taxes)	1.58%	3.03%	2.59%	[1]	Nov. 13, 2003	[1]

[1] Index returns are shown from November 30, 2003.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET NEW YORK MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW YORK MUNICIPAL BOND FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	NEW YORK MUNICIPAL BOND FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The highest level of current income exempt from federal and New York state and city income taxes as is consistent with the preservation of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	SHAREHOLDER FEES (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 17% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	17.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The New York Municipal Bond Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in investment grade municipal securities that pay interest that is exempt from federal and New York state and city income taxes. The principal issuers of these securities are state and local governments and their agencies located in New York, as well as in Puerto Rico and other U.S. territories and possessions. The Fund uses a Sub-Adviser to manage the Fund's portfolio under the general supervision of SIMC. The Sub-Adviser selects securities based on its view on the future direction of interest rates and the shape of the yield curve, as well as its views on credit quality and sector allocation issues. Where possible, the Sub-Adviser will attempt to acquire securities that are underpriced relative to other eligible securities. The Sub-Adviser will strive to maintain an average weighted portfolio maturity of three to ten years. The Fund may, to a limited extent, invest in securities subject to the alternative minimum tax or in debt securities subject to federal and New York state and city income taxes. The Fund may also invest in municipal securities rated below investment grade (junk bonds).
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Below Investment Grade Securities Risk -- Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. Liquidity Risk -- The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance. Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. New York Investment Risk -- The Fund's performance will be affected by the fiscal and economic health of the State of New York, its political subdivisions, municipalities, agencies and authorities and political and regulatory developments affecting New York municipal issuers. Non-Diversified Risk -- The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. Loss of money is a risk of investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Loss of money is a risk of investing in the Fund.
Risk Nondiversified Status [Text]	rr_RiskNondiversifiedStatus	The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 5.32% (09/30/09) Worst Quarter: -2.86% (12/31/10) The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012 was 3.20%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	reflects no deduction for fees, expenses or taxes
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
STET NEW YORK MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW YORK MUNICIPAL BOND FUND | Barclays Capital MF New York Intermediate Municipal Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Barclays Capital MF New York Intermediate Municipal Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	9.77%
5 Years	rr_AverageAnnualReturnYear05	6.20%
10 Years	rr_AverageAnnualReturnYear10	5.56%
Since Inception	rr_AverageAnnualReturnSinceInception	5.38%	[1]
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 18, 1998	[1]
STET NEW YORK MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW YORK MUNICIPAL BOND FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	rr_RedemptionFeeOverRedemption	(0.50%)
Management Fees	rr_ManagementFeesOverAssets	0.33%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.54%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.87%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	89
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	278
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	482
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,073
Annual Return 2002	rr_AnnualReturn2002	9.61%
Annual Return 2003	rr_AnnualReturn2003	5.00%
Annual Return 2004	rr_AnnualReturn2004	2.53%
Annual Return 2005	rr_AnnualReturn2005	1.08%
Annual Return 2006	rr_AnnualReturn2006	3.48%
Annual Return 2007	rr_AnnualReturn2007	4.01%
Annual Return 2008	rr_AnnualReturn2008	0.67%
Annual Return 2009	rr_AnnualReturn2009	9.64%
Annual Return 2010	rr_AnnualReturn2010	2.98%
Annual Return 2011	rr_AnnualReturn2011	7.96%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	3.20%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	5.32%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2010
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(2.86%)
Label	rr_AverageAnnualReturnLabel	Class A Shares Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	7.96%
5 Years	rr_AverageAnnualReturnYear05	5.00%
10 Years	rr_AverageAnnualReturnYear10	4.65%
Since Inception	rr_AverageAnnualReturnSinceInception	4.60%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 18, 1998
STET NEW YORK MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW YORK MUNICIPAL BOND FUND | CLASS A | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	7.80%
5 Years	rr_AverageAnnualReturnYear05	4.93%
10 Years	rr_AverageAnnualReturnYear10	4.56%
Since Inception	rr_AverageAnnualReturnSinceInception	4.52%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 18, 1998
STET NEW YORK MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW YORK MUNICIPAL BOND FUND | CLASS A | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares
1 Year	rr_AverageAnnualReturnYear01	6.41%
5 Years	rr_AverageAnnualReturnYear05	4.75%
10 Years	rr_AverageAnnualReturnYear10	4.46%
Since Inception	rr_AverageAnnualReturnSinceInception	4.44%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 18, 1998

[1] Index returns are shown from August 31, 1998.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET MASSACHUSETTS MUNICIPAL BOND FUND (Prospectus Summary) | STET MASSACHUSETTS MUNICIPAL BOND FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	MASSACHUSETTS MUNICIPAL BOND FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The highest level of current income exempt from federal and Massachusetts state income taxes as is consistent with the preservation of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	SHAREHOLDER FEES (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 10% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	10.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Massachusetts Municipal Bond Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in investment grade municipal securities that pay interest that is exempt from federal and Massachusetts state income taxes. The principal issuers of these securities are state and local governments and their agencies located in Massachusetts, as well as in Puerto Rico and other U.S. territories and possessions. The Fund uses a Sub-Adviser to manage the Fund's portfolio under the general supervision of SIMC. The Sub-Adviser selects securities based on its view on the future direction of interest rates and the shape of the yield curve, as well as its views on credit quality and sector allocation issues. Where possible, the Sub-Adviser will attempt to acquire securities that are underpriced relative to other eligible securities. The Sub-Adviser will strive to maintain an average weighted portfolio maturity of three to ten years. The Fund may, to a limited extent, invest in securities subject to the alternative minimum tax or in debt securities subject to federal and Massachusetts state income taxes. The Fund may also invest in municipal securities rated below investment grade (junk bonds).
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Below Investment Grade Securities Risk -- Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk- - The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. Liquidity Risk -- The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance. Massachusetts Investment Risk -- The Fund's performance will be affected by the fiscal and economic health of the Commonwealth of Massachusetts, its political subdivisions, municipalities, agencies and authorities and political and regulatory developments affecting Massachusetts municipal issuers.    Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. Non-Diversified Risk -- The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. Loss of money is a risk of investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Loss of money is a risk of investing in the Fund.
Risk Nondiversified Status [Text]	rr_RiskNondiversifiedStatus	The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 5.73% (09/30/09) Worst Quarter: -3.45% (12/31/10) The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012 was 3.54%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	reflects no deduction for fees, expenses or taxes
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
STET MASSACHUSETTS MUNICIPAL BOND FUND (Prospectus Summary) | STET MASSACHUSETTS MUNICIPAL BOND FUND | Barclays Capital MF Massachusetts Intermediate Municipal Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Barclays Capital MF Massachusetts Intermediate Municipal Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	10.74%
5 Years	rr_AverageAnnualReturnYear05	6.55%
10 Years	rr_AverageAnnualReturnYear10	5.72%
Since Inception	rr_AverageAnnualReturnSinceInception	5.52%	[1]
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 19, 1998	[1]
STET MASSACHUSETTS MUNICIPAL BOND FUND (Prospectus Summary) | STET MASSACHUSETTS MUNICIPAL BOND FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	rr_RedemptionFeeOverRedemption	(0.50%)
Management Fees	rr_ManagementFeesOverAssets	0.33%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.53%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.86%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	88
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	274
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	477
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,061
Annual Return 2002	rr_AnnualReturn2002	9.72%
Annual Return 2003	rr_AnnualReturn2003	4.63%
Annual Return 2004	rr_AnnualReturn2004	2.83%
Annual Return 2005	rr_AnnualReturn2005	1.40%
Annual Return 2006	rr_AnnualReturn2006	3.68%
Annual Return 2007	rr_AnnualReturn2007	4.06%
Annual Return 2008	rr_AnnualReturn2008	0.71%
Annual Return 2009	rr_AnnualReturn2009	10.24%
Annual Return 2010	rr_AnnualReturn2010	3.13%
Annual Return 2011	rr_AnnualReturn2011	9.89%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	3.54%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	5.73%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2010
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(3.45%)
Label	rr_AverageAnnualReturnLabel	Class A Shares Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	9.89%
5 Years	rr_AverageAnnualReturnYear05	5.54%
10 Years	rr_AverageAnnualReturnYear10	4.98%
Since Inception	rr_AverageAnnualReturnSinceInception	4.76%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 19, 1998
STET MASSACHUSETTS MUNICIPAL BOND FUND (Prospectus Summary) | STET MASSACHUSETTS MUNICIPAL BOND FUND | CLASS A | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	9.79%
5 Years	rr_AverageAnnualReturnYear05	5.49%
10 Years	rr_AverageAnnualReturnYear10	4.85%
Since Inception	rr_AverageAnnualReturnSinceInception	4.66%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 19, 1998
STET MASSACHUSETTS MUNICIPAL BOND FUND (Prospectus Summary) | STET MASSACHUSETTS MUNICIPAL BOND FUND | CLASS A | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares
1 Year	rr_AverageAnnualReturnYear01	7.57%
5 Years	rr_AverageAnnualReturnYear05	5.22%
10 Years	rr_AverageAnnualReturnYear10	4.73%
Since Inception	rr_AverageAnnualReturnSinceInception	4.57%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 19, 1998

[1] Index returns are shown from August 31, 1998.

XML

STET PENNSYLVANIA MUNICIPAL BOND FUND (First Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND

PENNSYLVANIA MUNICIPAL BOND FUND

Investment Goal

Current income exempt from federal and Pennsylvania state income taxes
consistent with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy
and hold Fund shares.

SHAREHOLDER FEES (fees paid directly from your investment)

Shareholder Fees	STET PENNSYLVANIA MUNICIPAL BOND FUND CLASS A
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	0.50%

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET PENNSYLVANIA MUNICIPAL BOND FUND CLASS A
Management Fees	0.35%
Distribution (12b-1) Fees	none
Other Expenses	0.49%
Total Annual Fund Operating Expenses	0.84%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET PENNSYLVANIA MUNICIPAL BOND FUND CLASS A	86	268	466	1,037

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells
securities (or "turns over" its portfolio). A higher portfolio turnover rate may
indicate higher transaction costs and may result in higher taxes when Fund
shares are held in a taxable account. These costs, which are not reflected in
annual Fund operating expenses or in the Example, affect the Fund's performance.
During the most recent fiscal year, the Fund's portfolio turnover rate was 12%
of the average value of its portfolio.

Principal Investment Strategies

The Pennsylvania Municipal Bond Fund will invest, under normal circumstances, at
least 80% of its net assets (plus the amount of any borrowings for investment
purposes) in investment grade municipal securities that pay interest that is
exempt from federal and Pennsylvania state income taxes. The principal issuers
of these securities are state and local governments and their agencies located
in Pennsylvania, as well as in Puerto Rico and other U.S. territories and
possessions.

The Fund uses a Sub-Adviser to manage the Fund's portfolio under the general
supervision of SIMC. The Sub-Adviser selects securities based on its view on the
future direction of interest rates and the shape of the yield curve, as well as
its views on credit quality and sector allocation issues. Where possible, the
Sub-Adviser will attempt to acquire securities that are underpriced relative to
other eligible securities. The Sub-Adviser will strive to maintain an average
weighted portfolio maturity of seven years or less. The Fund may, to a limited
extent, invest in securities subject to the alternative minimum tax or in debt
securities subject to federal and Pennsylvania state income taxes. The Fund may
also invest in municipal securities rated below investment grade (junk bonds).

Principal Risks

Below Investment Grade Securities Risk -- Fixed income securities rated below
investment grade (junk bonds) involve greater risks of default or downgrade and
are more volatile than investment grade securities because the prospect for
repayment of principal and interest of many of these securities is speculative.

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced to
reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk -- The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well as
to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates.

Liquidity Risk -- The risk that certain securities may be difficult or impossible
to sell at the time and the price that the Fund would like. The Fund may have to
lower the price, sell other securities instead or forego an investment opportunity,
any of which could have a negative effect on Fund management or performance.
  
Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities, to
pay interest and principal on municipal debt. Poor statewide or local economic
results or changing political sentiments may reduce tax revenues and increase
the expenses of municipal issuers, making it more difficult for them to meet
their obligations. Actual or perceived erosion of the creditworthiness of
municipal issuers may reduce the value of the Fund's holdings. As a result, the
Fund will be more susceptible to factors that adversely affect issuers of
municipal obligations than a mutual fund that does not have as great a
concentration in municipal obligations. Also, there may be economic or political
changes that impact the ability of issuers of municipal securities to repay
principal and to make interest payments on securities owned by the Fund. Any
changes in the financial condition of municipal issuers may also adversely
affect the value of the Fund's securities.

Pennsylvania Investment Risk -- The Fund's performance will be affected by the
fiscal and economic health of the Commonwealth of Pennsylvania, its political
subdivisions, municipalities, agencies and authorities and political and
regulatory developments affecting Pennsylvania municipal issuers.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax,
including the federal alternative minimum tax.

Loss of money is a risk of investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance
from year to year for the past ten calendar years and by showing how the Fund's
average annual returns for 1, 5 and 10 years, and since the Fund's inception,
compared with those of a broad measure of market performance. The Fund's past
performance (before and after taxes) is not necessarily an indication of how the
Fund will perform in the future. For current performance information, please
call 1-800-DIAL-SEI.

Best Quarter: 5.17% (09/30/09)

Worst Quarter: -3.14% (12/31/10)

The Fund's Class A total return (pre-tax) from January 1, 2012
to September 30, 2012 was 3.62%.

Average Annual Total Returns (for the periods ended December 31, 2011)

After-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local
taxes. Your actual after-tax returns will depend on your tax situation and may
differ from those shown. After-tax returns shown are not relevant to investors
who hold their Fund shares through tax-deferred arrangements, such as 401(k)
plans or individual retirement accounts.

Average Annual Total Returns STET PENNSYLVANIA MUNICIPAL BOND FUND	Label	1 Year	5 Years	10 Years	Since Inception		Inception Date
CLASS A	Class A Shares Return Before Taxes	9.81%	4.52%	4.50%	4.44%		Aug. 26, 1998
CLASS A After Taxes on Distributions	Class A Shares Return After Taxes on Distributions	9.81%	4.51%	4.46%	4.40%		Aug. 26, 1998
CLASS A After Taxes on Distributions and Sales	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares	7.50%	4.38%	4.40%	4.37%		Aug. 26, 1998
Barclays Capital MF Pennsylvania Intermediate Municipal Index	Barclays Capital MF Pennsylvania Intermediate Municipal Index (reflects no deduction for fees, expenses or taxes)	10.18%	6.21%	5.52%	5.31%	[1]	Aug. 26, 1998	[1]

[1] Index returns are shown from August 31, 1998.

XML

STET NEW JERSEY MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW JERSEY MUNICIPAL BOND FUND

NEW JERSEY MUNICIPAL BOND FUND

Investment Goal

The highest level of current income exempt from federal and New Jersey
state income taxes as is consistent with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold
Fund shares.

SHAREHOLDER FEES (fees paid directly from your investment)

Shareholder Fees	STET NEW JERSEY MUNICIPAL BOND FUND CLASS A
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	0.50%

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET NEW JERSEY MUNICIPAL BOND FUND CLASS A
Management Fees	0.33%
Distribution (12b-1) Fees	none
Other Expenses	0.53%
Total Annual Fund Operating Expenses	0.86%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET NEW JERSEY MUNICIPAL BOND FUND CLASS A	88	274	477	1,061

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells
securities (or "turns over" its portfolio). A higher portfolio turnover rate
may indicate higher transaction costs and may result in higher taxes when Fund
shares are held in a taxable account. These costs, which are not reflected in
annual Fund operating expenses or in the Example, affect the Fund's performance.
During the most recent fiscal year, the Fund's portfolio turnover rate was 16%
of the average value of its portfolio.

Principal Investment Strategies

The New Jersey Municipal Bond Fund will invest, under normal circumstances, at
least 80% of its net assets (plus the amount of any borrowings for investment
purposes) in investment grade municipal securities that pay interest that is
exempt from federal and New Jersey state income taxes. The principal issuers of
these securities are state and local governments and their agencies located in
New Jersey, as well as in Puerto Rico and other U.S. territories and
possessions.

The Fund uses a Sub-Adviser to manage the Fund's portfolio under the general
supervision of SIMC. The Sub-Adviser selects securities based on its view on the
future direction of interest rates and the shape of the yield curve, as well as
its views on credit quality and sector allocation issues. Where possible, the
Sub-Adviser will attempt to acquire securities that are underpriced relative to
other eligible securities. The Sub-Adviser will strive to maintain an average
weighted portfolio maturity of three to ten years. The Fund may, to a limited
extent, invest in securities subject to the alternative minimum tax or in debt
securities subject to federal and New Jersey state income taxes. The Fund may
also invest in municipal securities rated below investment grade (junk bonds).

Principal Risks

Below Investment Grade Securities Risk -- Fixed income securities rated below
investment grade (junk bonds) involve greater risks of default or downgrade and
are more volatile than investment grade securities because the prospect for
repayment of principal and interest of many of these securities is speculative.

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced to
reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk -- The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well
as to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates.

Liquidity Risk -- The risk that certain securities may be difficult or impossible
to sell at the time and the price that the Fund would like. The Fund may have to
lower the price, sell other securities instead or forego an investment
opportunity, any of which could have a negative effect on Fund management or
performance.

Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities,
to pay interest and principal on municipal debt. Poor statewide or local economic
results or changing political sentiments may reduce tax revenues and increase the
expenses of municipal issuers, making it more difficult for them to meet their
obligations. Actual or perceived erosion of the creditworthiness of municipal
issuers may reduce the value of the Fund's holdings. As a result, the Fund will
be more susceptible to factors that adversely affect issuers of municipal
obligations than a mutual fund that does not have as great a concentration in
municipal obligations. Also, there may be economic or political changes that
impact the ability of issuers of municipal securities to repay principal and to
make interest payments on securities owned by the Fund. Any changes in the
financial condition of municipal issuers may also adversely affect the value of
the Fund's securities.

New Jersey Investment Risk -- The Fund's performance will be affected by the
fiscal and economic health of the State of New Jersey, its political
subdivisions, municipalities, agencies and authorities and political and
regulatory developments affecting New Jersey municipal issuers.

Non-Diversified Risk -- The Fund is non-diversified, which means that it may
invest in the securities of relatively few issuers. As a result, the Fund may
be more susceptible to a single adverse economic or political occurrence affecting
one or more of these issuers and may experience increased volatility due to its
investments in those securities.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax, including
the federal alternative minimum tax.

Loss of money is a risk of investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance from
year to year for the past ten calendar years and by showing how the Fund's
average annual returns for 1, 5 and 10 years, and since the Fund's inception,
compared with those of a broad measure of market performance. The Fund's past
performance (before and after taxes) is not necessarily an indication of how the
Fund will perform in the future. For current performance information, please
call 1-800-DIAL-SEI.

Best Quarter: 4.48% (09/30/09)

Worst Quarter: -2.67% (12/31/10)

The Fund's Class A total return (pre-tax) from January 1, 2012
to September 30, 2012 was 3.19%.

Average Annual Total Returns (for the periods ended December 31, 2011)

After-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local
taxes. Your actual after-tax returns will depend on your tax situation and may
differ from those shown. After-tax returns shown are not relevant to investors
who hold their Fund shares through tax-deferred arrangements, such as 401(k)
plans or individual retirement accounts.

Average Annual Total Returns STET NEW JERSEY MUNICIPAL BOND FUND	Label	1 Year	5 Years	10 Years	Since Inception		Inception Date
CLASS A	Class A Shares Return Before Taxes	7.61%	4.72%	4.24%	4.27%		Aug. 18, 1998
CLASS A After Taxes on Distributions	Class A Shares Return After Taxes on Distributions	7.60%	4.71%	4.17%	4.21%		Aug. 18, 1998
CLASS A After Taxes on Distributions and Sales	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares	6.04%	4.51%	4.09%	4.14%		Aug. 18, 1998
Barclays Capital 3-10 Year Intermediate Municipal Blend Index	Barclays Capital 3-10 Year Intermediate Municipal Blend Index (reflects no deduction for fees, expenses or taxes)	8.56%	5.72%	5.09%	5.03%	[1]	Aug. 18, 1998	[1]

[1] Index returns are shown from August 31, 1998.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET INTERMEDIATE TERM MUNICIPAL FUND (Prospectus Summary) | STET INTERMEDIATE TERM MUNICIPAL FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	INTERMEDIATE-TERM MUNICIPAL FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The highest level of income exempt from federal income tax as is consistent with the preservation of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	SHAREHOLDER FEES (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 27% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	27.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Intermediate-Term Municipal Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in investment grade municipal securities that pay interest that is exempt from federal income tax. The principal issuers of these securities are state and local governments and their agencies located in any of the fifty states, the District of Columbia, Puerto Rico and other U.S. territories and possessions. The Fund uses a multi-manager approach, relying on a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage the Fund's portfolio under the general supervision of SEI Investments Management Corporation, the Fund's adviser (SIMC). To a limited extent, SIMC may also directly manage a portion of the Fund's portfolio. The Sub-Advisers and, to the extent applicable, SIMC select securities based on their views on the future direction of interest rates and the shape of the yield curve, as well as their views on credit quality and sector allocation issues. Where possible, the Sub-Advisers and, to the extent applicable, SIMC will attempt to acquire securities that are underpriced relative to other eligible securities. The Sub-Advisers and, to the extent applicable, SIMC will strive to maintain an average dollar-weighted portfolio maturity of three to ten years for the Fund's entire portfolio. The Fund may, to a limited extent, invest in securities subject to the alternative minimum tax or in debt securities subject to federal income tax. The Fund may also invest in municipal securities rated below investment grade (junk bonds).
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Below Investment Grade Securities Risk -- Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates.    Liquidity Risk -- The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance. Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. Loss of money is a risk of investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Loss of money is a risk of investing in the Fund.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 6.42% (09/30/09) Worst Quarter: -3.11% (12/31/10) The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012 was 4.75%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	reflects no deduction for fees, expenses or taxes
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
STET INTERMEDIATE TERM MUNICIPAL FUND (Prospectus Summary) | STET INTERMEDIATE TERM MUNICIPAL FUND | Barclays Capital 3-15 Year Intermediate Municipal Blend Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Barclays Capital 3-15 Year Intermediate Municipal Blend Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	9.63%
5 Years	rr_AverageAnnualReturnYear05	5.74%
10 Years	rr_AverageAnnualReturnYear10	5.35%
Since Inception	rr_AverageAnnualReturnSinceInception		[1]
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 1989	[1]
STET INTERMEDIATE TERM MUNICIPAL FUND (Prospectus Summary) | STET INTERMEDIATE TERM MUNICIPAL FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $25 million within any thirty (30) day period)	rr_RedemptionFeeOverRedemption	(0.50%)
Management Fees	rr_ManagementFeesOverAssets	0.33%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.53%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.86%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	88
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	274
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	477
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,061
Annual Return 2002	rr_AnnualReturn2002	8.87%
Annual Return 2003	rr_AnnualReturn2003	4.15%
Annual Return 2004	rr_AnnualReturn2004	2.64%
Annual Return 2005	rr_AnnualReturn2005	1.33%
Annual Return 2006	rr_AnnualReturn2006	3.87%
Annual Return 2007	rr_AnnualReturn2007	2.64%
Annual Return 2008	rr_AnnualReturn2008	(0.90%)
Annual Return 2009	rr_AnnualReturn2009	10.65%
Annual Return 2010	rr_AnnualReturn2010	3.37%
Annual Return 2011	rr_AnnualReturn2011	9.09%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	4.75%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	6.42%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2010
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(3.11%)
Label	rr_AverageAnnualReturnLabel	Class A Shares Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	9.09%
5 Years	rr_AverageAnnualReturnYear05	4.88%
10 Years	rr_AverageAnnualReturnYear10	4.51%
Since Inception	rr_AverageAnnualReturnSinceInception	5.24%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 1989
STET INTERMEDIATE TERM MUNICIPAL FUND (Prospectus Summary) | STET INTERMEDIATE TERM MUNICIPAL FUND | CLASS A | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	9.08%
5 Years	rr_AverageAnnualReturnYear05	4.88%
10 Years	rr_AverageAnnualReturnYear10	4.42%
Since Inception	rr_AverageAnnualReturnSinceInception	5.17%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 1989
STET INTERMEDIATE TERM MUNICIPAL FUND (Prospectus Summary) | STET INTERMEDIATE TERM MUNICIPAL FUND | CLASS A | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares
1 Year	rr_AverageAnnualReturnYear01	7.10%
5 Years	rr_AverageAnnualReturnYear05	4.68%
10 Years	rr_AverageAnnualReturnYear10	4.34%
Since Inception	rr_AverageAnnualReturnSinceInception	5.11%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 05, 1989

[1] The Barclays Capital 3-15 Year Intermediate Municipal Blend Index returns for the "Since Inception" period are not provided since index returns are not available prior to June 30, 1993.

XML

STET TAX FREE FUND (Prospectus Summary) | STET TAX FREE FUND

TAX FREE FUND

Investment Goal

Preserving principal value and maintaining a high degree of liquidity
while providing current income exempt from federal income taxes.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold
Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET TAX FREE FUND CLASS A
Management Fees	0.04%
Distribution (12b-1) Fees	none
Other Expenses	0.65%
Total Annual Fund Operating Expenses	0.69%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET TAX FREE FUND CLASS A	70	221	384	859

Principal Investment Strategies

The Tax Free Fund will invest, under normal circumstances, at least 80% of its
net assets (plus the amount of any borrowings for investment purposes) in
municipal money market securities (i) that pay interest that is exempt from
federal income taxes and (ii) the interest on which is not a preference item for
purposes of the federal alternative minimum tax. The principal issuers of these
securities are state and local governments and their agencies located in any of
the fifty states, the District of Columbia, Puerto Rico and other U.S.
territories and possessions.

The Fund uses a sub-adviser (the Sub-Adviser) to manage the Fund's portfolio
under the general supervision of SEI Investments Management Corporation, the
Fund's adviser (SIMC). The Sub-Adviser seeks to purchase liquid securities
with appropriate maturities (i.e., that meet the maturity requirements imposed
by Rule 2a-7 under the Investment Company Act of 1940, as amended) that offer
competitive yields and that are issued by financially sound issuers. The
Sub-Adviser also considers sector allocation and relative valuations in
selecting securities for the Fund.

The Fund invests in high quality, short-term debt securities, commonly known as
money market instruments. These include municipal bonds, notes, tax-exempt
commercial paper and industrial development bonds. The Fund may, to a limited
extent, invest in certain taxable securities and repurchase agreements, as well
as in securities subject to the alternative minimum tax or in taxable municipal
securities. The Fund follows strict Securities and Exchange Commission (SEC)
rules about the credit quality, maturity and diversification of its investments.

Principal Risks

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced to
reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk -- The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well
as to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Income Risk -- An investment in the Fund is subject to income risk, which is the
possibility that the Fund's yield will decline due to falling interest rates.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates. A rise in interest rates typically causes a
fall in the value of fixed income securities in which the Fund invests, while a
fall in interest rates typically causes a rise in the value of such securities.
During periods when interest rates are low, the Fund's yield (and total return)
also will be low and the income generated by the Fund may not be sufficient to
offset all or a significant portion of the Fund's expenses, which could impair
the Fund's ability to provide a positive yield and maintain a stable $1.00 share
price.

Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities,
to pay interest and principal on municipal debt. Poor statewide or local
economic results or changing political sentiments may reduce tax revenues and
increase the expenses of municipal issuers, making it more difficult for them
to meet their obligations. Actual or perceived erosion of the creditworthiness
of municipal issuers may reduce the value of the Fund's holdings. As a result,
the Fund will be more susceptible to factors that adversely affect issuers of
municipal obligations than a mutual fund that does not have as great a
concentration in municipal obligations. Also, there may be economic or political
changes that impact the ability of issuers of municipal securities to repay
principal and to make interest payments on securities owned by the Fund. Any
changes in the financial condition of municipal issuers may also adversely
affect the value of the Fund's securities.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.
  
Redemption Risk -- The Fund may experience periods of heavy redemptions that
could cause the Fund to liquidate its assets at inopportune times or at a loss
or depressed value, particularly during periods of declining or illiquid
markets. This could have a significant adverse effect on the Fund's ability to
maintain a stable $1.00 share price, and, in extreme circumstances, could cause
the Fund to suspend redemptions and liquidate completely.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax,
including the federal alternative minimum tax.

An investment in the Fund is not insured or guaranteed by the Federal Deposit
Insurance Corporation (FDIC) or any other government agency. Although the Fund
seeks to preserve the value of your investment at $1.00 per share, it is
possible to lose money by investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance
from year to year for the past ten calendar years and by showing the Fund's
average annual returns for 1, 5 and 10 years, and since the Fund's inception.
The Fund's past performance (before and after taxes) is not necessarily an
indication of how the Fund will perform in the future. For current performance
information, please call 1-800-DIAL-SEI.

Best Quarter: 0.84% (06/30/07)

Worst Quarter: 0.00% (03/31/11)

The Fund's Class A total return (pre-tax) from January 1, 2012 to
September 30, 2012 was 0.01%.

Average Annual Total Returns (for the periods ended December 31, 2011)

Average Annual Total Returns	Label	1 Year	5 Years	10 Years	Since Inception	Inception Date
STET TAX FREE FUND CLASS A	Class A Shares	0.01%	1.13%	1.33%	3.04%	Nov. 12, 1982

Please call 1-800-DIAL-SEI to obtain the Fund's current yield.

XML

STET INTERMEDIATE TERM MUNICIPAL FUND (Prospectus Summary) | STET INTERMEDIATE TERM MUNICIPAL FUND

INTERMEDIATE-TERM MUNICIPAL FUND

Investment Goal

The highest level of income exempt from federal income tax as is consistent with
the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold
Fund shares.

SHAREHOLDER FEES (fees paid directly from your investment)

Shareholder Fees	STET INTERMEDIATE TERM MUNICIPAL FUND CLASS A
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $25 million within any thirty (30) day period)	0.50%

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET INTERMEDIATE TERM MUNICIPAL FUND CLASS A
Management Fees	0.33%
Distribution (12b-1) Fees	none
Other Expenses	0.53%
Total Annual Fund Operating Expenses	0.86%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET INTERMEDIATE TERM MUNICIPAL FUND CLASS A	88	274	477	1,061

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells
securities (or "turns over" its portfolio). A higher portfolio turnover rate
may indicate higher transaction costs and may result in higher taxes when Fund
shares are held in a taxable account. These costs, which are not reflected in
annual Fund operating expenses or in the Example, affect the Fund's performance.
During the most recent fiscal year, the Fund's portfolio turnover rate was 27%
of the average value of its portfolio.

Principal Investment Strategies

The Intermediate-Term Municipal Fund will invest, under normal circumstances, at
least 80% of its net assets (plus the amount of any borrowings for investment
purposes) in investment grade municipal securities that pay interest that is
exempt from federal income tax. The principal issuers of these securities are
state and local governments and their agencies located in any of the fifty
states, the District of Columbia, Puerto Rico and other U.S. territories and
possessions.

The Fund uses a multi-manager approach, relying on a number of sub-advisers
(each, a Sub-Adviser and collectively, the Sub-Advisers) with differing
investment philosophies to manage the Fund's portfolio under the general
supervision of SEI Investments Management Corporation, the Fund's adviser
(SIMC). To a limited extent, SIMC may also directly manage a portion of the
Fund's portfolio. The Sub-Advisers and, to the extent applicable, SIMC select
securities based on their views on the future direction of interest rates and
the shape of the yield curve, as well as their views on credit quality and
sector allocation issues. Where possible, the Sub-Advisers and, to the extent
applicable, SIMC will attempt to acquire securities that are underpriced
relative to other eligible securities. The Sub-Advisers and, to the extent
applicable, SIMC will strive to maintain an average dollar-weighted portfolio
maturity of three to ten years for the Fund's entire portfolio. The Fund may,
to a limited extent, invest in securities subject to the alternative minimum
tax or in debt securities subject to federal income tax. The Fund may also
invest in municipal securities rated below investment grade (junk bonds).

Principal Risks

Below Investment Grade Securities Risk -- Fixed income securities rated below
investment grade (junk bonds) involve greater risks of default or downgrade and
are more volatile than investment grade securities because the prospect for
repayment of principal and interest of many of these securities is speculative.

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced to
reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk -- The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well
as to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates.
  
Liquidity Risk -- The risk that certain securities may be difficult or impossible
to sell at the time and the price that the Fund would like. The Fund may have to
lower the price, sell other securities instead or forego an investment
opportunity, any of which could have a negative effect on Fund management or
performance.

Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities,
to pay interest and principal on municipal debt. Poor statewide or local
economic results or changing political sentiments may reduce tax revenues and
increase the expenses of municipal issuers, making it more difficult for them
to meet their obligations. Actual or perceived erosion of the creditworthiness
of municipal issuers may reduce the value of the Fund's holdings. As a result,
the Fund will be more susceptible to factors that adversely affect issuers of
municipal obligations than a mutual fund that does not have as great a
concentration in municipal obligations. Also, there may be economic or political
changes that impact the ability of issuers of municipal securities to repay
principal and to make interest payments on securities owned by the Fund. Any
changes in the financial condition of municipal issuers may also adversely
affect the value of the Fund's securities.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax, including
the federal alternative minimum tax.

Loss of money is a risk of investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance
from year to year for the past ten calendar years and by showing how the
Fund's average annual returns for 1, 5 and 10 years, and since the Fund's
inception, compared with those of a broad measure of market performance. The
Fund's past performance (before and after taxes) is not necessarily an
indication of how the Fund will perform in the future. For current
performance information, please call 1-800-DIAL-SEI.

Best Quarter: 6.42% (09/30/09)

Worst Quarter: -3.11% (12/31/10)

The Fund's Class A total return (pre-tax) from January 1, 2012
to September 30, 2012 was 4.75%.

Average Annual Total Returns (for the periods ended December 31, 2011)

After-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local
taxes. Your actual after-tax returns will depend on your tax situation and may
differ from those shown. After-tax returns shown are not relevant to investors
who hold their Fund shares through tax-deferred arrangements, such as 401(k)
plans or individual retirement accounts.

Average Annual Total Returns STET INTERMEDIATE TERM MUNICIPAL FUND	Label	1 Year	5 Years	10 Years	Since Inception		Inception Date
CLASS A	Class A Shares Return Before Taxes	9.09%	4.88%	4.51%	5.24%		Sep. 05, 1989
CLASS A After Taxes on Distributions	Class A Shares Return After Taxes on Distributions	9.08%	4.88%	4.42%	5.17%		Sep. 05, 1989
CLASS A After Taxes on Distributions and Sales	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares	7.10%	4.68%	4.34%	5.11%		Sep. 05, 1989
Barclays Capital 3-15 Year Intermediate Municipal Blend Index	Barclays Capital 3-15 Year Intermediate Municipal Blend Index (reflects no deduction for fees, expenses or taxes)	9.63%	5.74%	5.35%		[1]	Sep. 05, 1989	[1]

[1] The Barclays Capital 3-15 Year Intermediate Municipal Blend Index returns for the "Since Inception" period are not provided since index returns are not available prior to June 30, 1993.

XML

STET INSTITUTIONAL TAX FREE FUND (First Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND

INSTITUTIONAL TAX FREE FUND

Investment Goal

Preserving principal value and maintaining a high degree of liquidity
while providing current income exempt from federal income taxes.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold
Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET INSTITUTIONAL TAX FREE FUND CLASS A
Management Fees	0.04%
Distribution (12b-1) Fees	none
Other Expenses	0.65%
Total Annual Fund Operating Expenses	0.69%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET INSTITUTIONAL TAX FREE FUND CLASS A	70	221	384	859

Principal Investment Strategies

The Institutional Tax Free Fund will invest, under normal circumstances, at
least 80% of its net assets (plus the amount of any borrowings for investment
purposes) in municipal money market securities (i) that pay interest that is
exempt from federal income taxes and (ii) the interest on which is not a
preference item for purposes of the federal alternative minimum tax. The
principal issuers of these securities are state and local governments and their
agencies located in any of the fifty states, the District of Columbia, Puerto
Rico and other U.S. territories and possessions.

The Fund uses a sub-adviser (the Sub-Adviser) to manage the Fund's portfolio
under the general supervision of SEI Investments Management Corporation, the
Fund's adviser (SIMC). The Sub-Adviser seeks to purchase liquid securities
with appropriate maturities (i.e., that meet the maturity requirements imposed
by Rule 2a-7 under the Investment Company Act of 1940, as amended) that offer
competitive yields and that are issued by financially sound issuers. The
Sub-Adviser also considers sector allocation and relative valuations in
selecting securities for the Fund.
  
The Fund invests in high quality, short-term debt securities, commonly known as
money market instruments. These include municipal bonds, notes, tax-exempt
commercial paper and industrial development bonds. The Fund may, to a limited
extent, invest in certain taxable securities and repurchase agreements, as well
as in securities subject to the alternative minimum tax or in taxable municipal
securities. The Fund follows strict Securities and Exchange Commission (SEC)
rules about the credit quality, maturity and diversification of its investments.

Principal Risks

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced
to reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk -- The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well as
to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Income Risk -- An investment in the Fund is subject to income risk, which is the
possibility that the Fund's yield will decline due to falling interest rates.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates. A rise in interest rates typically causes a
fall in the value of fixed income securities in which the Fund invests, while a
fall in interest rates typically causes a rise in the value of such securities.
During periods when interest rates are low, the Fund's yield (and total return)
also will be low and the income generated by the Fund may not be sufficient to
offset all or a significant portion of the Fund's expenses, which could impair
the Fund's ability to provide a positive yield and maintain a stable $1.00 share
price.

Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities,
to pay interest and principal on municipal debt. Poor statewide or local
economic results or changing political sentiments may reduce tax revenues and
increase the expenses of municipal issuers, making it more difficult for them
to meet their obligations. Actual or perceived erosion of the creditworthiness
of municipal issuers may reduce the value of the Fund's holdings. As a result,
the Fund will be more susceptible to factors that adversely affect issuers of
municipal obligations than a mutual fund that does not have as great a
concentration in municipal obligations. Also, there may be economic or political
changes that impact the ability of issuers of municipal securities to repay
principal and to make interest payments on securities owned by the Fund. Any
changes in the financial condition of municipal issuers may also adversely
affect the value of the Fund's securities.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.
  
Redemption Risk -- The Fund may experience periods of heavy redemptions that
could cause the Fund to liquidate its assets at inopportune times or at a loss
or depressed value, particularly during periods of declining or illiquid
markets. This could have a significant adverse effect on the Fund's ability to
maintain a stable $1.00 share price, and, in extreme circumstances, could cause
the Fund to suspend redemptions and liquidate completely.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax,
including the federal alternative minimum tax.

An investment in the Fund is not insured or guaranteed by the Federal Deposit
Insurance Corporation (FDIC) or any other government agency. Although the Fund
seeks to preserve the value of your investment at $1.00 per share, it is
possible to lose money by investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance
from year to year for the past ten calendar years and by showing the Fund's
average annual returns for 1, 5 and 10 years, and since the Fund's inception.
The Fund's past performance (before and after taxes) is not necessarily an
indication of how the Fund will perform in the future. For current performance
information, please call 1-800-DIAL-SEI.

Best Quarter: 0.87% (06/30/07)

Worst Quarter: 0.01% (06/30/11)

The Fund's Class A total return (pre-tax) from January 1, 2012 to
September 30, 2012 was 0.02%.

Average Annual Total Returns (for the periods ended December 31, 2011)

Average Annual Total Returns	Label	1 Year	5 Years	10 Years	Since Inception	Inception Date
STET INSTITUTIONAL TAX FREE FUND CLASS A	Class A Shares	0.06%	1.22%	1.45%	3.16%	Nov. 03, 1982

Please call 1-800-DIAL-SEI to obtain the Fund's current yield.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET CALIFORNIA MUNICIPAL BOND FUND (Prospectus Summary) | STET CALIFORNIA MUNICIPAL BOND FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	CALIFORNIA MUNICIPAL BOND FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The highest level of current income exempt from federal and California state income taxes as is consistent with the preservation of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	SHAREHOLDER FEES (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 20% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	20.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The California Municipal Bond Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in investment grade municipal securities that pay interest that is exempt from federal and California state income taxes. The principal issuers of these securities are state and local governments and their agencies located in California, as well as in Puerto Rico and other U.S. territories and possessions. The Fund uses a Sub-Adviser to manage the Fund's portfolio under the general supervision of SIMC. The Sub-Adviser selects securities based on its view on the future direction of interest rates and the shape of the yield curve, as well as its views on credit quality and sector allocation issues. Where possible, the Sub-Adviser will attempt to acquire securities that are underpriced relative to other eligible securities. The Sub-Adviser will strive to maintain an average weighted portfolio maturity of three to ten years. The Fund may, to a limited extent, invest in securities subject to the alternative minimum tax or in debt securities subject to federal and California state income taxes. The Fund may also invest in municipal securities rated below investment grade (junk bonds).
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Below Investment Grade Securities Risk -- Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. California Investment Risk -- The Fund's performance will be affected by the fiscal and economic health of the State of California, its political subdivisions, municipalities, agencies and authorities and political and regulatory developments affecting California municipal issuers. Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. Liquidity Risk -- The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.    Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. Non-Diversified Risk -- The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. Loss of money is a risk of investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Loss of money is a risk of investing in the Fund.
Risk Nondiversified Status [Text]	rr_RiskNondiversifiedStatus	The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 6.20% (09/30/09) Worst Quarter: -3.23% (12/31/10) The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012 was 4.18%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	reflects no deduction for fees, expenses or taxes
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
STET CALIFORNIA MUNICIPAL BOND FUND (Prospectus Summary) | STET CALIFORNIA MUNICIPAL BOND FUND | Barclays Capital MF California Intermediate Municipal Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Barclays Capital MF California Intermediate Municipal Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	11.20%
5 Years	rr_AverageAnnualReturnYear05	6.28%
10 Years	rr_AverageAnnualReturnYear10	5.54%
Since Inception	rr_AverageAnnualReturnSinceInception	5.35%	[1]
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 19, 1998	[1]
STET CALIFORNIA MUNICIPAL BOND FUND (Prospectus Summary) | STET CALIFORNIA MUNICIPAL BOND FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	rr_RedemptionFeeOverRedemption	(0.50%)
Management Fees	rr_ManagementFeesOverAssets	0.33%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.53%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.86%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	88
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	274
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	477
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,061
Annual Return 2002	rr_AnnualReturn2002	7.81%
Annual Return 2003	rr_AnnualReturn2003	4.04%
Annual Return 2004	rr_AnnualReturn2004	3.14%
Annual Return 2005	rr_AnnualReturn2005	1.18%
Annual Return 2006	rr_AnnualReturn2006	3.37%
Annual Return 2007	rr_AnnualReturn2007	3.64%
Annual Return 2008	rr_AnnualReturn2008	0.89%
Annual Return 2009	rr_AnnualReturn2009	7.63%
Annual Return 2010	rr_AnnualReturn2010	3.73%
Annual Return 2011	rr_AnnualReturn2011	9.45%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	4.18%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	6.20%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2010
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(3.23%)
Label	rr_AverageAnnualReturnLabel	Class A Shares Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	9.45%
5 Years	rr_AverageAnnualReturnYear05	5.02%
10 Years	rr_AverageAnnualReturnYear10	4.45%
Since Inception	rr_AverageAnnualReturnSinceInception	4.66%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 19, 1998
STET CALIFORNIA MUNICIPAL BOND FUND (Prospectus Summary) | STET CALIFORNIA MUNICIPAL BOND FUND | CLASS A | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	9.45%
5 Years	rr_AverageAnnualReturnYear05	5.00%
10 Years	rr_AverageAnnualReturnYear10	4.37%
Since Inception	rr_AverageAnnualReturnSinceInception	4.57%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 19, 1998
STET CALIFORNIA MUNICIPAL BOND FUND (Prospectus Summary) | STET CALIFORNIA MUNICIPAL BOND FUND | CLASS A | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares
1 Year	rr_AverageAnnualReturnYear01	7.27%
5 Years	rr_AverageAnnualReturnYear05	4.78%
10 Years	rr_AverageAnnualReturnYear10	4.28%
Since Inception	rr_AverageAnnualReturnSinceInception	4.48%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 19, 1998

[1] Index returns are shown from August 31, 1998.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET NEW JERSEY MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW JERSEY MUNICIPAL BOND FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	NEW JERSEY MUNICIPAL BOND FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The highest level of current income exempt from federal and New Jersey state income taxes as is consistent with the preservation of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	SHAREHOLDER FEES (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 16% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	16.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The New Jersey Municipal Bond Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in investment grade municipal securities that pay interest that is exempt from federal and New Jersey state income taxes. The principal issuers of these securities are state and local governments and their agencies located in New Jersey, as well as in Puerto Rico and other U.S. territories and possessions. The Fund uses a Sub-Adviser to manage the Fund's portfolio under the general supervision of SIMC. The Sub-Adviser selects securities based on its view on the future direction of interest rates and the shape of the yield curve, as well as its views on credit quality and sector allocation issues. Where possible, the Sub-Adviser will attempt to acquire securities that are underpriced relative to other eligible securities. The Sub-Adviser will strive to maintain an average weighted portfolio maturity of three to ten years. The Fund may, to a limited extent, invest in securities subject to the alternative minimum tax or in debt securities subject to federal and New Jersey state income taxes. The Fund may also invest in municipal securities rated below investment grade (junk bonds).
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Below Investment Grade Securities Risk -- Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. Liquidity Risk -- The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance. Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. New Jersey Investment Risk -- The Fund's performance will be affected by the fiscal and economic health of the State of New Jersey, its political subdivisions, municipalities, agencies and authorities and political and regulatory developments affecting New Jersey municipal issuers. Non-Diversified Risk -- The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. Loss of money is a risk of investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Loss of money is a risk of investing in the Fund.
Risk Nondiversified Status [Text]	rr_RiskNondiversifiedStatus	The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 4.48% (09/30/09) Worst Quarter: -2.67% (12/31/10) The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012 was 3.19%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	reflects no deduction for fees, expenses or taxes
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
STET NEW JERSEY MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW JERSEY MUNICIPAL BOND FUND | Barclays Capital 3-10 Year Intermediate Municipal Blend Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Barclays Capital 3-10 Year Intermediate Municipal Blend Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	8.56%
5 Years	rr_AverageAnnualReturnYear05	5.72%
10 Years	rr_AverageAnnualReturnYear10	5.09%
Since Inception	rr_AverageAnnualReturnSinceInception	5.03%	[1]
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 18, 1998	[1]
STET NEW JERSEY MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW JERSEY MUNICIPAL BOND FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	rr_RedemptionFeeOverRedemption	(0.50%)
Management Fees	rr_ManagementFeesOverAssets	0.33%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.53%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.86%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	88
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	274
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	477
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,061
Annual Return 2002	rr_AnnualReturn2002	8.34%
Annual Return 2003	rr_AnnualReturn2003	4.00%
Annual Return 2004	rr_AnnualReturn2004	2.31%
Annual Return 2005	rr_AnnualReturn2005	1.04%
Annual Return 2006	rr_AnnualReturn2006	3.28%
Annual Return 2007	rr_AnnualReturn2007	4.01%
Annual Return 2008	rr_AnnualReturn2008	1.61%
Annual Return 2009	rr_AnnualReturn2009	7.74%
Annual Return 2010	rr_AnnualReturn2010	2.78%
Annual Return 2011	rr_AnnualReturn2011	7.61%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	3.19%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	4.48%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2010
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(2.67%)
Label	rr_AverageAnnualReturnLabel	Class A Shares Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	7.61%
5 Years	rr_AverageAnnualReturnYear05	4.72%
10 Years	rr_AverageAnnualReturnYear10	4.24%
Since Inception	rr_AverageAnnualReturnSinceInception	4.27%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 18, 1998
STET NEW JERSEY MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW JERSEY MUNICIPAL BOND FUND | CLASS A | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	7.60%
5 Years	rr_AverageAnnualReturnYear05	4.71%
10 Years	rr_AverageAnnualReturnYear10	4.17%
Since Inception	rr_AverageAnnualReturnSinceInception	4.21%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 18, 1998
STET NEW JERSEY MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW JERSEY MUNICIPAL BOND FUND | CLASS A | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares
1 Year	rr_AverageAnnualReturnYear01	6.04%
5 Years	rr_AverageAnnualReturnYear05	4.51%
10 Years	rr_AverageAnnualReturnYear10	4.09%
Since Inception	rr_AverageAnnualReturnSinceInception	4.14%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 18, 1998

[1] Index returns are shown from August 31, 1998.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
Document Type	dei_DocumentType	485BPOS
Document Period End Date	dei_DocumentPeriodEndDate	Aug. 31, 2012
Registrant Name	dei_EntityRegistrantName	SEI TAX EXEMPT TRUST
Central Index Key	dei_EntityCentralIndexKey	0000701817
Amendment Flag	dei_AmendmentFlag	false
Document Creation Date	dei_DocumentCreationDate	Dec. 27, 2012
Document Effective Date	dei_DocumentEffectiveDate	Dec. 31, 2012
STET INTERMEDIATE TERM MUNICIPAL FUND (Prospectus Summary) | STET INTERMEDIATE TERM MUNICIPAL FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	SEIMX
STET SHORT DURATION MUNICIPAL FUND (Prospectus Summary) | STET SHORT DURATION MUNICIPAL FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	SUMAX
STET CALIFORNIA MUNICIPAL BOND FUND (Prospectus Summary) | STET CALIFORNIA MUNICIPAL BOND FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	SBDAX
STET MASSACHUSETTS MUNICIPAL BOND FUND (Prospectus Summary) | STET MASSACHUSETTS MUNICIPAL BOND FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	SMAAX
STET NEW JERSEY MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW JERSEY MUNICIPAL BOND FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	SENJX
STET NEW YORK MUNICIPAL BOND FUND (Prospectus Summary) | STET NEW YORK MUNICIPAL BOND FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	SENYX
STET PENNSYLVANIA MUNICIPAL BOND FUND (First Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	SEPAX
STET TAX-ADVANTAGED INCOME FUND (Prospectus Summary) | STET TAX-ADVANTAGED INCOME FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	SEATX
STET PENNSYLVANIA MUNICIPAL BOND FUND (Second Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND | CLASS B
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	SEIPX
STET INSTITUTIONAL TAX FREE FUND (First Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	TXWXX
STET INSTITUTIONAL TAX FREE FUND (Second Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND | CLASS B
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	SITXX
STET INSTITUTIONAL TAX FREE FUND (Third Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND | CLASS C
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	SFCXX
STET TAX FREE FUND (Prospectus Summary) | STET TAX FREE FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	TXEXX

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STET MASSACHUSETTS MUNICIPAL BOND FUND (Prospectus Summary) | STET MASSACHUSETTS MUNICIPAL BOND FUND

MASSACHUSETTS MUNICIPAL BOND FUND

Investment Goal

The highest level of current income exempt from federal and Massachusetts
state income taxes as is consistent with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy
and hold Fund shares.

SHAREHOLDER FEES (fees paid directly from your investment)

Shareholder Fees	STET MASSACHUSETTS MUNICIPAL BOND FUND CLASS A
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	0.50%

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET MASSACHUSETTS MUNICIPAL BOND FUND CLASS A
Management Fees	0.33%
Distribution (12b-1) Fees	none
Other Expenses	0.53%
Total Annual Fund Operating Expenses	0.86%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET MASSACHUSETTS MUNICIPAL BOND FUND CLASS A	88	274	477	1,061

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells
securities (or "turns over" its portfolio). A higher portfolio turnover rate
may indicate higher transaction costs and may result in higher taxes when Fund
shares are held in a taxable account. These costs, which are not reflected in
annual Fund operating expenses or in the Example, affect the Fund's performance.
During the most recent fiscal year, the Fund's portfolio turnover rate was 10%
of the average value of its portfolio.

Principal Investment Strategies

The Massachusetts Municipal Bond Fund will invest, under normal circumstances,
at least 80% of its net assets (plus the amount of any borrowings for investment
purposes) in investment grade municipal securities that pay interest that is
exempt from federal and Massachusetts state income taxes. The principal issuers
of these securities are state and local governments and their agencies located
in Massachusetts, as well as in Puerto Rico and other U.S. territories and
possessions.

The Fund uses a Sub-Adviser to manage the Fund's portfolio under the general
supervision of SIMC. The Sub-Adviser selects securities based on its view on the
future direction of interest rates and the shape of the yield curve, as well as
its views on credit quality and sector allocation issues. Where possible, the
Sub-Adviser will attempt to acquire securities that are underpriced relative to
other eligible securities. The Sub-Adviser will strive to maintain an average
weighted portfolio maturity of three to ten years. The Fund may, to a limited
extent, invest in securities subject to the alternative minimum tax or in debt
securities subject to federal and Massachusetts state income taxes. The Fund may
also invest in municipal securities rated below investment grade (junk bonds).

Principal Risks

Below Investment Grade Securities Risk -- Fixed income securities rated below
investment grade (junk bonds) involve greater risks of default or downgrade and
are more volatile than investment grade securities because the prospect for
repayment of principal and interest of many of these securities is speculative.

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced to
reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk- - The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well
as to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates.

Liquidity Risk -- The risk that certain securities may be difficult or impossible
to sell at the time and the price that the Fund would like. The Fund may have to
lower the price, sell other securities instead or forego an investment
opportunity, any of which could have a negative effect on Fund management or
performance.

Massachusetts Investment Risk -- The Fund's performance will be affected by the
fiscal and economic health of the Commonwealth of Massachusetts, its political
subdivisions, municipalities, agencies and authorities and political and
regulatory developments affecting Massachusetts municipal issuers.
  
Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities,
to pay interest and principal on municipal debt. Poor statewide or local
economic results or changing political sentiments may reduce tax revenues and
increase the expenses of municipal issuers, making it more difficult for them
to meet their obligations. Actual or perceived erosion of the creditworthiness
of municipal issuers may reduce the value of the Fund's holdings. As a result,
the Fund will be more susceptible to factors that adversely affect issuers of
municipal obligations than a mutual fund that does not have as great a
concentration in municipal obligations. Also, there may be economic or political
changes that impact the ability of issuers of municipal securities to repay
principal and to make interest payments on securities owned by the Fund. Any
changes in the financial condition of municipal issuers may also adversely
affect the value of the Fund's securities.

Non-Diversified Risk -- The Fund is non-diversified, which means that it may
invest in the securities of relatively few issuers. As a result, the Fund may be
more susceptible to a single adverse economic or political occurrence affecting
one or more of these issuers and may experience increased volatility due to its
investments in those securities.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax,
including the federal alternative minimum tax.

Loss of money is a risk of investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance from
year to year for the past ten calendar years and by showing how the Fund's
average annual returns for 1, 5 and 10 years, and since the Fund's inception,
compared with those of a broad measure of market performance. The Fund's past
performance (before and after taxes) is not necessarily an indication of how the
Fund will perform in the future. For current performance information, please
call 1-800-DIAL-SEI.

Best Quarter: 5.73% (09/30/09)

Worst Quarter: -3.45% (12/31/10)

The Fund's Class A total return (pre-tax) from January 1, 2012
to September 30, 2012 was 3.54%.

Average Annual Total Returns (for the periods ended December 31, 2011)

After-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local
taxes. Your actual after-tax returns will depend on your tax situation and may
differ from those shown. After-tax returns shown are not relevant to investors
who hold their Fund shares through tax-deferred arrangements, such as 401(k)
plans or individual retirement accounts.

Average Annual Total Returns STET MASSACHUSETTS MUNICIPAL BOND FUND	Label	1 Year	5 Years	10 Years	Since Inception		Inception Date
CLASS A	Class A Shares Return Before Taxes	9.89%	5.54%	4.98%	4.76%		Aug. 19, 1998
CLASS A After Taxes on Distributions	Class A Shares Return After Taxes on Distributions	9.79%	5.49%	4.85%	4.66%		Aug. 19, 1998
CLASS A After Taxes on Distributions and Sales	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares	7.57%	5.22%	4.73%	4.57%		Aug. 19, 1998
Barclays Capital MF Massachusetts Intermediate Municipal Index	Barclays Capital MF Massachusetts Intermediate Municipal Index (reflects no deduction for fees, expenses or taxes)	10.74%	6.55%	5.72%	5.52%	[1]	Aug. 19, 1998	[1]

[1] Index returns are shown from August 31, 1998.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET SHORT DURATION MUNICIPAL FUND (Prospectus Summary) | STET SHORT DURATION MUNICIPAL FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	SHORT DURATION MUNICIPAL FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	High level of income exempt from federal income tax consistent with the preservation of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	SHAREHOLDER FEES (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 42% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	42.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Short Duration Municipal Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in investment grade municipal securities that pay interest that is exempt from federal income tax. The principal issuers of these securities are state and local governments and their agencies located in any of the fifty states, the District of Columbia, Puerto Rico and other U.S. territories and possessions. Duration is a weighted average term-to-maturity of the security's cash flow. The weights are the present values of each cash flow as a percentage of the present value of all cash flows (i.e., the weights are the present value of each cash flow as a percentage of the bond's full price). The Fund uses one or more Sub-Advisers to manage the Fund's portfolio under the general supervision of SIMC. The Sub-Adviser selects securities based on its view on the future direction of interest rates and the shape of the yield curve, as well as its views on credit quality and sector allocation issues. Where possible, the Sub-Adviser will attempt to acquire securities that are underpriced relative to other eligible securities. The Sub-Adviser will strive to maintain a portfolio duration of three years or less. The Fund may, to a limited extent, invest in securities subject to the alternative minimum tax or in debt securities subject to federal income tax.
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. Liquidity Risk -- The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance. Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. Loss of money is a risk of investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Loss of money is a risk of investing in the Fund.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past eight calendar years and by showing how the Fund's average annual returns for 1 and 5 years, and since the Fund's inception, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past eight calendar years and by showing how the Fund's average annual returns for 1 and 5 years, and since the Fund's inception, compared with those of a broad measure of market performance.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 1.51% (12/31/08) Worst Quarter: -0.26% (06/30/04) The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012 was 0.79%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	reflects no deduction for fees, expenses or taxes
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
STET SHORT DURATION MUNICIPAL FUND (Prospectus Summary) | STET SHORT DURATION MUNICIPAL FUND | Barclays Capital 1-Year Municipal Bond Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Barclays Capital 1-Year Municipal Bond Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	1.58%
5 Years	rr_AverageAnnualReturnYear05	3.03%
Since Inception	rr_AverageAnnualReturnSinceInception	2.59%	[1]
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 13, 2003	[1]
STET SHORT DURATION MUNICIPAL FUND (Prospectus Summary) | STET SHORT DURATION MUNICIPAL FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $25 million within any thirty (30) day period)	rr_RedemptionFeeOverRedemption	(0.50%)
Management Fees	rr_ManagementFeesOverAssets	0.33%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.53%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.86%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	88
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	274
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	477
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,061
Annual Return 2004	rr_AnnualReturn2004	0.72%
Annual Return 2005	rr_AnnualReturn2005	1.42%
Annual Return 2006	rr_AnnualReturn2006	2.88%
Annual Return 2007	rr_AnnualReturn2007	3.77%
Annual Return 2008	rr_AnnualReturn2008	3.76%
Annual Return 2009	rr_AnnualReturn2009	3.42%
Annual Return 2010	rr_AnnualReturn2010	0.89%
Annual Return 2011	rr_AnnualReturn2011	1.52%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	0.79%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Dec. 31, 2008
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	1.51%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Jun. 30, 2004
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(0.26%)
Label	rr_AverageAnnualReturnLabel	Class A Shares Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	1.52%
5 Years	rr_AverageAnnualReturnYear05	2.66%
Since Inception	rr_AverageAnnualReturnSinceInception	2.28%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 13, 2003
STET SHORT DURATION MUNICIPAL FUND (Prospectus Summary) | STET SHORT DURATION MUNICIPAL FUND | CLASS A | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	1.51%
5 Years	rr_AverageAnnualReturnYear05	2.64%
Since Inception	rr_AverageAnnualReturnSinceInception	2.26%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 13, 2003
STET SHORT DURATION MUNICIPAL FUND (Prospectus Summary) | STET SHORT DURATION MUNICIPAL FUND | CLASS A | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares
1 Year	rr_AverageAnnualReturnYear01	1.44%
5 Years	rr_AverageAnnualReturnYear05	2.60%
Since Inception	rr_AverageAnnualReturnSinceInception	2.25%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 13, 2003

[1] Index returns are shown from November 30, 2003.

XML

STET CALIFORNIA MUNICIPAL BOND FUND (Prospectus Summary) | STET CALIFORNIA MUNICIPAL BOND FUND

CALIFORNIA MUNICIPAL BOND FUND

Investment Goal

The highest level of current income exempt from federal and California state
income taxes as is consistent with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold
Fund shares.

SHAREHOLDER FEES (fees paid directly from your investment)

Shareholder Fees	STET CALIFORNIA MUNICIPAL BOND FUND CLASS A
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	0.50%

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET CALIFORNIA MUNICIPAL BOND FUND CLASS A
Management Fees	0.33%
Distribution (12b-1) Fees	none
Other Expenses	0.53%
Total Annual Fund Operating Expenses	0.86%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET CALIFORNIA MUNICIPAL BOND FUND CLASS A	88	274	477	1,061

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells
securities (or "turns over" its portfolio). A higher portfolio turnover rate
may indicate higher transaction costs and may result in higher taxes when Fund
shares are held in a taxable account. These costs, which are not reflected in
annual Fund operating expenses or in the Example, affect the Fund's performance.
During the most recent fiscal year, the Fund's portfolio turnover rate was 20%
of the average value of its portfolio.

Principal Investment Strategies

The California Municipal Bond Fund will invest, under normal circumstances, at
least 80% of its net assets (plus the amount of any borrowings for investment
purposes) in investment grade municipal securities that pay interest that is
exempt from federal and California state income taxes. The principal issuers of
these securities are state and local governments and their agencies located in
California, as well as in Puerto Rico and other U.S. territories and
possessions.

The Fund uses a Sub-Adviser to manage the Fund's portfolio under the general
supervision of SIMC. The Sub-Adviser selects securities based on its view on the
future direction of interest rates and the shape of the yield curve, as well as
its views on credit quality and sector allocation issues. Where possible, the
Sub-Adviser will attempt to acquire securities that are underpriced relative to
other eligible securities. The Sub-Adviser will strive to maintain an average
weighted portfolio maturity of three to ten years. The Fund may, to a limited
extent, invest in securities subject to the alternative minimum tax or in debt
securities subject to federal and California state income taxes. The Fund may
also invest in municipal securities rated below investment grade (junk bonds).

Principal Risks

Below Investment Grade Securities Risk -- Fixed income securities rated below
investment grade (junk bonds) involve greater risks of default or downgrade and
are more volatile than investment grade securities because the prospect for
repayment of principal and interest of many of these securities is speculative.

California Investment Risk -- The Fund's performance will be affected by the
fiscal and economic health of the State of California, its political
subdivisions, municipalities, agencies and authorities and political and
regulatory developments affecting California municipal issuers.

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced to
reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk -- The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well as
to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates.

Liquidity Risk -- The risk that certain securities may be difficult or impossible
to sell at the time and the price that the Fund would like. The Fund may have to
lower the price, sell other securities instead or forego an investment
opportunity, any of which could have a negative effect on Fund management or
performance.
  
Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities, to
pay interest and principal on municipal debt. Poor statewide or local economic
results or changing political sentiments may reduce tax revenues and increase
the expenses of municipal issuers, making it more difficult for them to meet
their obligations. Actual or perceived erosion of the creditworthiness of
municipal issuers may reduce the value of the Fund's holdings. As a result, the
Fund will be more susceptible to factors that adversely affect issuers of
municipal obligations than a mutual fund that does not have as great a
concentration in municipal obligations. Also, there may be economic or political
changes that impact the ability of issuers of municipal securities to repay
principal and to make interest payments on securities owned by the Fund. Any
changes in the financial condition of municipal issuers may also adversely
affect the value of the Fund's securities.

Non-Diversified Risk -- The Fund is non-diversified, which means that it may
invest in the securities of relatively few issuers. As a result, the Fund may be
more susceptible to a single adverse economic or political occurrence affecting
one or more of these issuers and may experience increased volatility due to its
investments in those securities.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax,
including the federal alternative minimum tax.

Loss of money is a risk of investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance from
year to year for the past ten calendar years and by showing how the Fund's
average annual returns for 1, 5 and 10 years, and since the Fund's inception,
compared with those of a broad measure of market performance. The Fund's past
performance (before and after taxes) is not necessarily an indication of how the
Fund will perform in the future. For current performance information, please
call 1-800-DIAL-SEI.

Best Quarter: 6.20% (09/30/09)

Worst Quarter: -3.23% (12/31/10)

The Fund's Class A total return (pre-tax) from January 1, 2012 to
September 30, 2012 was 4.18%.

Average Annual Total Returns (for the periods ended December 31, 2011)

After-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local
taxes. Your actual after-tax returns will depend on your tax situation and may
differ from those shown. After-tax returns shown are not relevant to investors
who hold their Fund shares through tax-deferred arrangements, such as 401(k)
plans or individual retirement accounts.

Average Annual Total Returns STET CALIFORNIA MUNICIPAL BOND FUND	Label	1 Year	5 Years	10 Years	Since Inception		Inception Date
CLASS A	Class A Shares Return Before Taxes	9.45%	5.02%	4.45%	4.66%		Aug. 19, 1998
CLASS A After Taxes on Distributions	Class A Shares Return After Taxes on Distributions	9.45%	5.00%	4.37%	4.57%		Aug. 19, 1998
CLASS A After Taxes on Distributions and Sales	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares	7.27%	4.78%	4.28%	4.48%		Aug. 19, 1998
Barclays Capital MF California Intermediate Municipal Index	Barclays Capital MF California Intermediate Municipal Index (reflects no deduction for fees, expenses or taxes)	11.20%	6.28%	5.54%	5.35%	[1]	Aug. 19, 1998	[1]

[1] Index returns are shown from August 31, 1998.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET PENNSYLVANIA MUNICIPAL BOND FUND (Second Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	PENNSYLVANIA MUNICIPAL BOND FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Current income exempt from federal and Pennsylvania income taxes consistent with the preservation of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	SHAREHOLDER FEES (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 12% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	12.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Pennsylvania Municipal Bond Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in investment grade municipal securities that pay interest that is exempt from federal and Pennsylvania state income taxes. The principal issuers of these securities are state and local governments and their agencies located in Pennsylvania, as well as in Puerto Rico and other U.S. territories and possessions. The Fund uses a sub-adviser (the Sub-Adviser) to manage the Fund's portfolio under the general supervision of SEI Investments Management Corporation, the Fund's adviser (SIMC). The Sub-Adviser selects securities based on its view on the future direction of interest rates and the shape of the yield curve, as well as its views on credit quality and sector allocation issues. Where possible, the Sub-Adviser will attempt to acquire securities that are underpriced relative to other eligible securities. The Sub-Adviser will strive to maintain an average weighted portfolio maturity of seven years or less. The Fund may, to a limited extent, invest in securities subject to the alternative minimum tax or in debt securities subject to federal and Pennsylvania state income taxes. The Fund may also invest in municipal securities rated below investment grade (junk bonds).
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Below Investment Grade Securities Risk -- Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. Liquidity Risk -- The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance. Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. Pennsylvania Investment Risk -- The Fund's performance will be affected by the fiscal and economic health of the Commonwealth of Pennsylvania, its political subdivisions, municipalities, agencies and authorities and political and regulatory developments affecting Pennsylvania municipal issuers. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. Loss of money is a risk of investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Loss of money is a risk of investing in the Fund.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compared with those of a broad measure of market performance.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 5.30% (09/30/09) Worst Quarter: -3.10% (12/31/10) The Fund's Class B total return (pre-tax) from January 1, 2012 to September 30, 2012 was 3.74%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	reflects no deduction for fees, expenses or taxes
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
STET PENNSYLVANIA MUNICIPAL BOND FUND (Second Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND | Barclays Capital MF Pennsylvania Intermediate Municipal Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Barclays Capital MF Pennsylvania Intermediate Municipal Index (reflects no deduction for fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	10.18%
5 Years	rr_AverageAnnualReturnYear05	6.21%
10 Years	rr_AverageAnnualReturnYear10	5.52%
Average Annual Returns, Since Inception Secondary	ck0000701817_AverageAnnualReturnSinceInceptionSecondary		[1]
Average Annual Returns, Inception Date Secondary	ck0000701817_AverageAnnualReturnInceptionDateSecondary	Aug. 14, 1989	[1]
STET PENNSYLVANIA MUNICIPAL BOND FUND (Second Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND | CLASS B
Risk Return [Abstract]	rr_RiskReturnAbstract
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	rr_RedemptionFeeOverRedemption	(0.50%)
Management Fees	rr_ManagementFeesOverAssets	0.35%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.54%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.89%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	91
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	284
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	493
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,096
Annual Return 2002	rr_AnnualReturn2002	9.82%
Annual Return 2003	rr_AnnualReturn2003	4.87%
Annual Return 2004	rr_AnnualReturn2004	2.57%
Annual Return 2005	rr_AnnualReturn2005	2.13%
Annual Return 2006	rr_AnnualReturn2006	3.79%
Annual Return 2007	rr_AnnualReturn2007	3.63%
Annual Return 2008	rr_AnnualReturn2008	(1.40%)
Annual Return 2009	rr_AnnualReturn2009	8.27%
Annual Return 2010	rr_AnnualReturn2010	3.30%
Annual Return 2011	rr_AnnualReturn2011	9.86%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class B total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	3.74%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	5.30%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2010
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(3.10%)
Label	rr_AverageAnnualReturnLabel	Class B Shares Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	9.86%
5 Years	rr_AverageAnnualReturnYear05	4.66%
10 Years	rr_AverageAnnualReturnYear10	4.63%
Since Inception	rr_AverageAnnualReturnSinceInception	5.38%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 14, 1989
STET PENNSYLVANIA MUNICIPAL BOND FUND (Second Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND | CLASS B | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class B Shares Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	9.86%
5 Years	rr_AverageAnnualReturnYear05	4.65%
10 Years	rr_AverageAnnualReturnYear10	4.59%
Since Inception	rr_AverageAnnualReturnSinceInception	5.32%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 14, 1989
STET PENNSYLVANIA MUNICIPAL BOND FUND (Second Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND | CLASS B | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class B Shares Return After Taxes on Distributions and Sale of Fund Shares
1 Year	rr_AverageAnnualReturnYear01	7.59%
5 Years	rr_AverageAnnualReturnYear05	4.51%
10 Years	rr_AverageAnnualReturnYear10	4.54%
Since Inception	rr_AverageAnnualReturnSinceInception	5.28%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 14, 1989

[1] The Barclays Capital MF Pennsylvania Intermediate Municipal Index returns for the "Since Inception" period are not provided since index returns are not available prior to June 30, 1993.

XML

STET TAX-ADVANTAGED INCOME FUND (Prospectus Summary) | STET TAX-ADVANTAGED INCOME FUND

TAX-ADVANTAGED INCOME FUND

Investment Goal

Provide the highest level of income possible in a tax efficient manner.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold
Fund shares.

SHAREHOLDER FEES (fees paid directly from your investment)

Shareholder Fees	STET TAX-ADVANTAGED INCOME FUND CLASS A
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	0.50%

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses		STET TAX-ADVANTAGED INCOME FUND CLASS A
Management Fees		0.50%
Distribution (12b-1) Fees		none
Other Expenses		0.64%
Acquired Fund Fees and Expenses (AFFE)		0.01%
Total Annual Fund Operating Expenses	[1]	1.15%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET TAX-ADVANTAGED INCOME FUND CLASS A	117	365	633	1,398

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells
securities (or "turns over" its portfolio). A higher portfolio turnover rate
may indicate higher transaction costs and may result in higher taxes when Fund
shares are held in a taxable account. These costs, which are not reflected in
annual Fund operating expenses or in the Example, affect the Fund's performance.
During the most recent fiscal year, the Fund's portfolio turnover rate was 13%
of the average value of its portfolio.

Principal Investment Strategies

The Tax-Advantaged Income Fund will invest, under normal circumstances, at least
50% of its net assets in municipal securities that pay interest that is exempt
from federal income tax, including the alternative minimum tax. The principal
issuers of these securities are state and local governments and their agencies
located in any of the fifty states, as well as in Puerto Rico and other U.S.
territories and possessions. The Fund may invest more than 25% of its total
assets in bonds of issuers in California and New York. Under most market
conditions, a large percentage of the municipal securities in which the Fund
invests will be below investment grade (junk bonds), but the Fund, without
limitation, may invest in higher rated municipal securities.

To a lesser extent, the Fund will also invest in a full range of preferred stock
with an emphasis on preferred securities that, at the time of issuance, are
eligible to pay dividends that qualify for certain favorable federal income tax
treatment, such as dividends that are treated as qualified dividend income and
the dividend received deduction (in each instance, provided certain requirements
and holding periods are satisfied, see "Taxes"). Absent further legislation, the
favorable federal income tax rates applicable to qualified dividend income will
cease to apply in taxable years beginning after December 31, 2012 (for more
information, see "Taxes"). The amount invested in preferred stocks at any one
time will depend on the attractiveness of the after-tax income stream produced
by the preferred securities and will be less than 50% of the Fund's net assets.
It is possible that the Fund could own no preferred securities if municipal
securities produce a higher yield on an after-tax basis.

While a portion of the Fund may invest in securities other than municipal and
preferred securities, the Fund will seek to purchase securities that enjoy
preferential tax treatment. The Fund may also invest in convertible securities,
securities eligible for resale under Rule 144A of the Securities Act of 1933
and other privately placed securities, debt securities subject to federal
income tax, common stock and open and closed-end funds. SIMC may directly
invest up to 5% of the Fund's assets in closed-end bond funds.

The Fund uses a multi-manager approach to manage the Fund's portfolio under the
general supervision of SIMC. Each Sub-Adviser and, to the extent applicable,
SIMC selects securities based on its view on the future direction of interest
rates and the shape of the yield curve, as well as its views on credit quality
and sector allocation issues. Where possible, each Sub-Adviser and, to the
extent applicable, SIMC, will attempt to acquire securities that are underpriced
relative to other eligible securities. Each Sub-Adviser and, to the extent
applicable, SIMC, will seek to maintain duration of four to eleven years for the
Fund's entire portfolio. The Fund may invest in securities subject to the
alternative minimum tax or in taxable debt securities.

Principal Risks

Below Investment Grade Securities Risk -- Fixed income securities rated below
investment grade (junk bonds) involve greater risks of default or downgrade and
are more volatile than investment grade securities because the prospect for
repayment of principal and interest of many of these securities is speculative.

California/New York Investment Risk -- To the extent the Fund invests a material
portion of its assets in issuers of California or New York municipal securities,
the Fund's performance will be affected by the fiscal and economic health of
the States of California or New York, their political subdivisions,
municipalities, agencies and authorities and political and regulatory
developments affecting California or New York municipal issuers.

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced to
reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Convertible and Preferred Securities Risk -- Convertible and preferred securities
generally have less potential for gain or loss than common stocks. In addition,
convertible and preferred securities generally provide yields higher than the
underlying common stocks, but generally lower than comparable non-convertible
securities. Because of this higher yield, convertible and preferred securities
generally sell at a price above their "conversion value," which is the current
market value of the stock to be received upon conversion. The difference between
this conversion value and the price of convertible and preferred securities will
vary over time depending on changes in the value of the underlying common stocks
and interest rates. Convertible and preferred securities are also subject to
credit risk and are often lower-quality securities.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Equity Market Risk -- The risk that stock prices will fall over short or extended
periods of time.

Extension Risk -- The risk that rising interest rates may extend the duration of
a fixed income security, typically reducing the security's value.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates.

Investment Company Risk -- When the Fund invests in an investment company, in
addition to directly bearing the expenses associated with its own operations, it
will bear a pro rata portion of the investment company's expenses. In addition,
while the risks of owning shares of an investment company generally reflect the
risks of owning the underlying investments of the investment company, the Fund
may be subject to additional or different risks than if the Fund had invested
directly in the underlying investments. Closed-end investment companies issue a
fixed number of shares that trade on a stock exchange or over-the-counter at a
premium or a discount to their net asset value. As a result, a closed-end fund's
share price fluctuates based on what another investor is willing to pay rather
than on the market value of the securities in the fund.

Liquidity Risk -- The risk that certain securities may be difficult or impossible
to sell at the time and the price that the Fund would like. The Fund may have to
lower the price, sell other securities instead or forego an investment
opportunity, any of which could have a negative effect on Fund management or
performance.

Municipal Securities Risk -- Municipal securities, like other fixed income
securities, rise and fall in value in response to economic and market factors,
primarily changes in interest rates, and actual or perceived credit quality.
Rising interest rates will generally cause municipal securities to decline in
value. Longer-term securities respond more sharply to interest rate changes
than do shorter-term securities. A municipal security will also lose value if,
due to rating downgrades or other factors, there are concerns about the issuer's
current or future ability to make principal or interest payments. State and
local governments rely on taxes and, to some extent, revenues from private
projects financed by municipal securities, to pay interest and principal on
municipal debt. Poor statewide or local economic results or changing political
sentiments may reduce tax revenues and increase the expenses of municipal
issuers, making it more difficult for them to meet their obligations. Actual or
perceived erosion of the creditworthiness of municipal issuers may reduce the
value of the Fund's holdings. As a result, the Fund will be more susceptible to
factors that adversely affect issuers of municipal obligations than a mutual
fund that does not have as great a concentration in municipal obligations. Also,
there may be economic or political changes that impact the ability of issuers of
municipal securities to repay principal and to make interest payments on
securities owned by the Fund. Any changes in the financial condition of
municipal issuers may also adversely affect the value of the Fund's securities.

Non-Diversified Risk -- The Fund is non-diversified, which means that it may
invest in the securities of relatively few issuers. As a result, the Fund may be
more susceptible to a single adverse economic or political occurrence affecting
one or more of these issuers and may experience increased volatility due to its
investments in those securities.

Portfolio Turnover Risk -- Due to its investment strategy, the Fund may buy and
sell securities frequently. This may result in higher transaction costs and
additional capital gains tax liabilities.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.

Private Placements Risk -- Investment in privately placed securities may be
less liquid than in publicly traded securities. Although these securities may
be resold in privately negotiated transactions, the prices realized from these
sales could be less than those originally paid by the Fund or less than what
may be considered the fair value of such securities. Furthermore, companies
whose securities are not publicly traded may not be subject to the disclosure
and other investor protection requirements that might be applicable if their
securities were publicly traded.

Tax Risk -- In order to pay tax-exempt interest, tax-exempt securities must
meet certain legal requirements. Failure to meet such requirements may cause
the interest received and distributed by the Fund to shareholders to be
taxable. Changes or proposed changes in federal tax laws may cause the prices
of tax-exempt securities to fall. While the Fund intends, under normal
circumstances, to invest at least 50% of its net assets in municipal securities
that pay interest that is exempt from federal income tax in order to meet the
requirements necessary to pay out exempt-interest dividends to its shareholders,
if the Fund fails to meet this requirement, the income from all of its investments,
including its municipal securities, may be subject to federal income tax.

Loss of money is a risk of investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing the Fund's performance from year
to year for the past four calendar years and by showing how the Fund's
average annual returns for 1 year, and since the Fund's inception, compared
with those of a broad measure of market performance. The Fund's past performance
(before and after taxes) is not necessarily an indication of how the Fund will
perform in the future. For current performance information, please call
1-800-DIAL-SEI.

Best Quarter: 17.31% (06/30/09)

Worst Quarter: -11.47% (09/30/08)

The Fund's Class A total return (pre-tax) from January 1, 2012 to
September 30, 2012 was 13.11%.

Average Annual Total Returns (for the periods ended December 31, 2011)

This table compares the Fund's average annual total returns to those of a
broad-based index and the Fund's 60/40 Blended Benchmark, which consists of
the Barclays Capital High Yield Municipal Bond Index and the Barclays Capital
Municipal Bond Index. The Fund's Blended Benchmark is designed to reflect a
useful comparison to the Fund's overall performance and reflects the Fund's
investment strategy more accurately than the broad-based index.

After-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local taxes.
Your actual after-tax returns will depend on your tax situation and may differ
from those shown. After-tax returns shown are not relevant to investors who hold
their Fund shares through tax-deferred arrangements, such as 401(k) plans or
individual retirement accounts.

Average Annual Total Returns STET TAX-ADVANTAGED INCOME FUND	Label	1 Year	Since Inception		Inception Date
CLASS A	Class A Shares Return Before Taxes	5.70%	3.26%		Sep. 04, 2007
CLASS A After Taxes on Distributions	Class A Shares Return After Taxes on Distributions	5.03%	2.48%		Sep. 04, 2007
CLASS A After Taxes on Distributions and Sales	Class A Shares Return After Taxes on Distributions and Sale of Fund Shares	4.76%	2.71%		Sep. 04, 2007
Barclays Capital High Yield Municipal Bond Index	Barclays Capital High Yield Municipal Bond Index (reflects no deduction for fees, expenses or taxes)	9.25%	2.43%	[1]	Sep. 04, 2007	[1]
The Fund's 60/40 Blended Benchmark Return	The Fund's 60/40 Blended Benchmark Return (reflects no deduction for fees, expenses or taxes)	9.83%	3.81%	[1]	Sep. 04, 2007	[1]

[1] Because the Fund incurred AFFE during the most recent fiscal year, the operating expenses in this fee table will not correlate to the expense ratio in the Fund's financial statements (or the "Financial Highlights" section in the prospectus) because the financial statements include only the direct operating expenses incurred by the Fund, not the indirect costs of investing in other investment companies.

[1] Index returns are shown from September 30, 2007.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET TAX FREE FUND (Prospectus Summary) | STET TAX FREE FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	TAX FREE FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Preserving principal value and maintaining a high degree of liquidity while providing current income exempt from federal income taxes.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Tax Free Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in municipal money market securities (i) that pay interest that is exempt from federal income taxes and (ii) the interest on which is not a preference item for purposes of the federal alternative minimum tax. The principal issuers of these securities are state and local governments and their agencies located in any of the fifty states, the District of Columbia, Puerto Rico and other U.S. territories and possessions. The Fund uses a sub-adviser (the Sub-Adviser) to manage the Fund's portfolio under the general supervision of SEI Investments Management Corporation, the Fund's adviser (SIMC). The Sub-Adviser seeks to purchase liquid securities with appropriate maturities (i.e., that meet the maturity requirements imposed by Rule 2a-7 under the Investment Company Act of 1940, as amended) that offer competitive yields and that are issued by financially sound issuers. The Sub-Adviser also considers sector allocation and relative valuations in selecting securities for the Fund. The Fund invests in high quality, short-term debt securities, commonly known as money market instruments. These include municipal bonds, notes, tax-exempt commercial paper and industrial development bonds. The Fund may, to a limited extent, invest in certain taxable securities and repurchase agreements, as well as in securities subject to the alternative minimum tax or in taxable municipal securities. The Fund follows strict Securities and Exchange Commission (SEC) rules about the credit quality, maturity and diversification of its investments.
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Income Risk -- An investment in the Fund is subject to income risk, which is the possibility that the Fund's yield will decline due to falling interest rates. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. A rise in interest rates typically causes a fall in the value of fixed income securities in which the Fund invests, while a fall in interest rates typically causes a rise in the value of such securities. During periods when interest rates are low, the Fund's yield (and total return) also will be low and the income generated by the Fund may not be sufficient to offset all or a significant portion of the Fund's expenses, which could impair the Fund's ability to provide a positive yield and maintain a stable $1.00 share price. Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.    Redemption Risk -- The Fund may experience periods of heavy redemptions that could cause the Fund to liquidate its assets at inopportune times or at a loss or depressed value, particularly during periods of declining or illiquid markets. This could have a significant adverse effect on the Fund's ability to maintain a stable $1.00 share price, and, in extreme circumstances, could cause the Fund to suspend redemptions and liquidate completely. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Although the Fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the Fund.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 0.84% (06/30/07) Worst Quarter: 0.00% (03/31/11) The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012 was 0.01%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	Please call 1-800-DIAL-SEI to obtain the Fund's current yield.
STET TAX FREE FUND (Prospectus Summary) | STET TAX FREE FUND | CLASS A
Risk Return [Abstract]	rr_RiskReturnAbstract
Management Fees	rr_ManagementFeesOverAssets	0.04%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.65%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.69%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	70
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	221
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	384
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	859
Annual Return 2002	rr_AnnualReturn2002	1.15%
Annual Return 2003	rr_AnnualReturn2003	0.70%
Annual Return 2004	rr_AnnualReturn2004	0.81%
Annual Return 2005	rr_AnnualReturn2005	2.00%
Annual Return 2006	rr_AnnualReturn2006	3.04%
Annual Return 2007	rr_AnnualReturn2007	3.28%
Annual Return 2008	rr_AnnualReturn2008	2.00%
Annual Return 2009	rr_AnnualReturn2009	0.34%
Annual Return 2010	rr_AnnualReturn2010	0.04%
Annual Return 2011	rr_AnnualReturn2011	0.01%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class A total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	0.01%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2007
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	0.84%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2011
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	0.00%
Label	rr_AverageAnnualReturnLabel	Class A Shares
1 Year	rr_AverageAnnualReturnYear01	0.01%
5 Years	rr_AverageAnnualReturnYear05	1.13%
10 Years	rr_AverageAnnualReturnYear10	1.33%
Since Inception	rr_AverageAnnualReturnSinceInception	3.04%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 12, 1982

XML

STET PENNSYLVANIA MUNICIPAL BOND FUND (Second Prospectus Summary) | STET PENNSYLVANIA MUNICIPAL BOND FUND

PENNSYLVANIA MUNICIPAL BOND FUND

Investment Goal

Current income exempt from federal and Pennsylvania income taxes consistent
with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold
Fund shares.

SHAREHOLDER FEES (fees paid directly from your investment)

Shareholder Fees	STET PENNSYLVANIA MUNICIPAL BOND FUND CLASS B
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $10 million within any thirty (30) day period)	0.50%

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	STET PENNSYLVANIA MUNICIPAL BOND FUND CLASS B
Management Fees	0.35%
Distribution (12b-1) Fees	none
Other Expenses	0.54%
Total Annual Fund Operating Expenses	0.89%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds. The Example assumes that you
invest $10,000 in the Fund for the time periods indicated and then redeem all
of your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Fund's operating expenses
remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, with Redemption, 1 Year	Expense Example, with Redemption, 3 Years	Expense Example, with Redemption, 5 Years	Expense Example, with Redemption, 10 Years
STET PENNSYLVANIA MUNICIPAL BOND FUND CLASS B	91	284	493	1,096

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells
securities (or "turns over" its portfolio). A higher portfolio turnover rate
may indicate higher transaction costs and may result in higher taxes when Fund
shares are held in a taxable account. These costs, which are not reflected in
annual Fund operating expenses or in the Example, affect the Fund's performance.
During the most recent fiscal year, the Fund's portfolio turnover rate was 12%
of the average value of its portfolio.

Principal Investment Strategies

The Pennsylvania Municipal Bond Fund will invest, under normal circumstances, at
least 80% of its net assets (plus the amount of any borrowings for investment
purposes) in investment grade municipal securities that pay interest that is
exempt from federal and Pennsylvania state income taxes. The principal issuers
of these securities are state and local governments and their agencies located
in Pennsylvania, as well as in Puerto Rico and other U.S. territories and
possessions.

The Fund uses a sub-adviser (the Sub-Adviser) to manage the Fund's portfolio
under the general supervision of SEI Investments Management Corporation, the
Fund's adviser (SIMC). The Sub-Adviser selects securities based on its view on
the future direction of interest rates and the shape of the yield curve, as well
as its views on credit quality and sector allocation issues. Where possible, the
Sub-Adviser will attempt to acquire securities that are underpriced relative to
other eligible securities. The Sub-Adviser will strive to maintain an average
weighted portfolio maturity of seven years or less. The Fund may, to a limited
extent, invest in securities subject to the alternative minimum tax or in debt
securities subject to federal and Pennsylvania state income taxes. The Fund may
also invest in municipal securities rated below investment grade (junk bonds).

Principal Risks

Below Investment Grade Securities Risk -- Fixed income securities rated below
investment grade (junk bonds) involve greater risks of default or downgrade
and are more volatile than investment grade securities because the prospect
for repayment of principal and interest of many of these securities is
speculative.

Call Risk -- Issuers of callable bonds may call (redeem) securities with higher
coupons or interest rates before their maturity dates. The Fund may be forced to
reinvest the unanticipated proceeds at lower interest rates, resulting in a
decline in the Fund's income. Bonds may be called due to falling interest rates
or non-economical circumstances.

Credit Risk -- The Fund could lose money if the issuer or guarantor of a
portfolio security or a counterparty to a contract fails to make timely payment
or otherwise honor its obligations. If the Fund purchases securities supported
by credit enhancements from banks and other financial institutions, changes in
the credit quality of these institutions could cause losses to the Fund and
affect its share price.

Extension Risk -- The risk that rising interest rates may extend the duration
of a fixed income security, typically reducing the security's value.

Fixed Income Market Risk -- The prices of the Fund's fixed income securities
respond to economic developments, particularly interest rate changes, as well
as to perceptions about the creditworthiness of individual issuers, including
governments and their agencies. In addition, the Fund is subject to the risk
that tax-exempt fixed income securities may underperform other fixed income
market segments or the fixed income markets as a whole.

Interest Rate Risk -- The risk that the value of fixed income securities will
fall due to rising interest rates.

Liquidity Risk -- The risk that certain securities may be difficult or impossible
to sell at the time and the price that the Fund would like. The Fund may have to
lower the price, sell other securities instead or forego an investment opportunity,
any of which could have a negative effect on Fund management or performance.

Municipal Securities Risk -- State and local governments rely on taxes and, to
some extent, revenues from private projects financed by municipal securities,
to pay interest and principal on municipal debt. Poor statewide or local
economic results or changing political sentiments may reduce tax revenues and
increase the expenses of municipal issuers, making it more difficult for them
to meet their obligations. Actual or perceived erosion of the creditworthiness
of municipal issuers may reduce the value of the Fund's holdings. As a result,
the Fund will be more susceptible to factors that adversely affect issuers of
municipal obligations than a mutual fund that does not have as great a
concentration in municipal obligations. Also, there may be economic or political
changes that impact the ability of issuers of municipal securities to repay
principal and to make interest payments on securities owned by the Fund. Any
changes in the financial condition of municipal issuers may also adversely
affect the value of the Fund's securities.

Pennsylvania Investment Risk -- The Fund's performance will be affected by the
fiscal and economic health of the Commonwealth of Pennsylvania, its political
subdivisions, municipalities, agencies and authorities and political and
regulatory developments affecting Pennsylvania municipal issuers.

Prepayment Risk -- The risk that, with declining interest rates, fixed income
securities with stated interest rates may have the principal paid earlier than
expected, requiring the Fund to invest the proceeds at generally lower interest
rates.

Taxation Risk -- The Fund may invest a portion of its assets in securities that
generate income that is subject to federal, state and local income tax, including
the federal alternative minimum tax.

Loss of money is a risk of investing in the Fund.

Performance Information

The bar chart and the performance table below provide some indication of the
risks of investing in the Fund by showing changes in the Fund's performance
from year to year for the past ten calendar years and by showing how the Fund's
average annual returns for 1, 5 and 10 years, and since the Fund's inception,
compared with those of a broad measure of market performance. The Fund's past
performance (before and after taxes) is not necessarily an indication of how
the Fund will perform in the future. For current performance information,
please call 1-800-DIAL-SEI.

Best Quarter: 5.30% (09/30/09)

Worst Quarter: -3.10% (12/31/10)

The Fund's Class B total return (pre-tax) from January 1, 2012 to
September 30, 2012 was 3.74%.

Average Annual Total Returns (for the periods ended December 31, 2011)

After-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local
taxes. Your actual after-tax returns will depend on your tax situation and may
differ from those shown. After-tax returns shown are not relevant to investors
who hold their Fund shares through tax-deferred arrangements, such as 401(k)
plans or individual retirement accounts.

Average Annual Total Returns STET PENNSYLVANIA MUNICIPAL BOND FUND	Label	1 Year	5 Years	10 Years	Since Inception	Inception Date	Average Annual Returns, Since Inception Secondary		Average Annual Returns, Inception Date Secondary
CLASS B	Class B Shares Return Before Taxes	9.86%	4.66%	4.63%	5.38%	Aug. 14, 1989
CLASS B After Taxes on Distributions	Class B Shares Return After Taxes on Distributions	9.86%	4.65%	4.59%	5.32%	Aug. 14, 1989
CLASS B After Taxes on Distributions and Sales	Class B Shares Return After Taxes on Distributions and Sale of Fund Shares	7.59%	4.51%	4.54%	5.28%	Aug. 14, 1989
Barclays Capital MF Pennsylvania Intermediate Municipal Index	Barclays Capital MF Pennsylvania Intermediate Municipal Index (reflects no deduction for fees, expenses or taxes)	10.18%	6.21%	5.52%				[1]	Aug. 14, 1989	[1]

[1] The Barclays Capital MF Pennsylvania Intermediate Municipal Index returns for the "Since Inception" period are not provided since index returns are not available prior to June 30, 1993.

XML

Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2012
STET INSTITUTIONAL TAX FREE FUND (Third Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	INSTITUTIONAL TAX FREE FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Preserving principal value and maintaining a high degree of liquidity while providing current income exempt from federal income taxes.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Institutional Tax Free Fund will invest, under normal circumstances, at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in municipal money market securities (i) that pay interest that is exempt from federal income taxes and (ii) the interest on which is not a preference item for purposes of the federal alternative minimum tax. The principal issuers of these securities are state and local governments and their agencies located in any of the fifty states, the District of Columbia, Puerto Rico and other U.S. territories and possessions. The Fund uses a sub-adviser (the Sub-Adviser) to manage the Fund's portfolio under the general supervision of SEI Investments Management Corporation, the Fund's adviser (SIMC). The Sub-Adviser seeks to purchase liquid securities with appropriate maturities (i.e., that meet the maturity requirements imposed by Rule 2a-7 under the Investment Company Act of 1940, as amended) that offer competitive yields and that are issued by financially sound issuers. The Sub-Adviser also considers sector allocation and relative valuations in selecting securities for the Fund.    The Fund invests in high quality, short-term debt securities, commonly known as money market instruments. These include municipal bonds, notes, tax-exempt commercial paper and industrial development bonds. The Fund may, to a limited extent, invest in certain taxable securities and repurchase agreements, as well as in securities subject to the alternative minimum tax or in taxable municipal securities. The Fund follows strict Securities and Exchange Commission (SEC) rules about the credit quality, maturity and diversification of its investments.
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Call Risk -- Issuers of callable bonds may call (redeem) securities with higher coupons or interest rates before their maturity dates. The Fund may be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund's income. Bonds may be called due to falling interest rates or non-economical circumstances. Credit Risk -- The Fund could lose money if the issuer or guarantor of a portfolio security or a counterparty to a contract fails to make timely payment or otherwise honor its obligations. If the Fund purchases securities supported by credit enhancements from banks and other financial institutions, changes in the credit quality of these institutions could cause losses to the Fund and affect its share price. Extension Risk -- The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Fixed Income Market Risk -- The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. In addition, the Fund is subject to the risk that tax-exempt fixed income securities may underperform other fixed income market segments or the fixed income markets as a whole. Income Risk -- An investment in the Fund is subject to income risk, which is the possibility that the Fund's yield will decline due to falling interest rates. Interest Rate Risk -- The risk that the value of fixed income securities will fall due to rising interest rates. A rise in interest rates typically causes a fall in the value of fixed income securities in which the Fund invests, while a fall in interest rates typically causes a rise in the value of such securities. During periods when interest rates are low, the Fund's yield (and total return) also will be low and the income generated by the Fund may not be sufficient to offset all or a significant portion of the Fund's expenses, which could impair the Fund's ability to provide a positive yield and maintain a stable $1.00 share price. Municipal Securities Risk -- State and local governments rely on taxes and, to some extent, revenues from private projects financed by municipal securities, to pay interest and principal on municipal debt. Poor statewide or local economic results or changing political sentiments may reduce tax revenues and increase the expenses of municipal issuers, making it more difficult for them to meet their obligations. Actual or perceived erosion of the creditworthiness of municipal issuers may reduce the value of the Fund's holdings. As a result, the Fund will be more susceptible to factors that adversely affect issuers of municipal obligations than a mutual fund that does not have as great a concentration in municipal obligations. Also, there may be economic or political changes that impact the ability of issuers of municipal securities to repay principal and to make interest payments on securities owned by the Fund. Any changes in the financial condition of municipal issuers may also adversely affect the value of the Fund's securities. Prepayment Risk -- The risk that, with declining interest rates, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. Redemption Risk -- The Fund may experience periods of heavy redemptions that could cause the Fund to liquidate its assets at inopportune times or at a loss or depressed value, particularly during periods of declining or illiquid markets. This could have a significant adverse effect on the Fund's ability to maintain a stable $1.00 share price, and, in extreme circumstances, could cause the Fund to suspend redemptions and liquidate completely. Taxation Risk -- The Fund may invest a portion of its assets in securities that generate income that is subject to federal, state and local income tax, including the federal alternative minimum tax. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the Fund.
Risk Lose Money [Text]	rr_RiskLoseMoney	Although the Fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the Fund.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 0.74% (09/30/07) Worst Quarter: 0.01% (03/31/10) The Fund's Class C total return (pre-tax) from January 1, 2012 to September 30, 2012 was 0.01%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	Please call 1-800-DIAL-SEI to obtain the Fund's current yield.
STET INSTITUTIONAL TAX FREE FUND (Third Prospectus Summary) | STET INSTITUTIONAL TAX FREE FUND | CLASS C
Risk Return [Abstract]	rr_RiskReturnAbstract
Management Fees	rr_ManagementFeesOverAssets	0.04%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.90%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.94%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	96
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	300
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	520
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,155
Annual Return 2002	rr_AnnualReturn2002	0.80%
Annual Return 2003	rr_AnnualReturn2003	0.35%
Annual Return 2004	rr_AnnualReturn2004	0.45%
Annual Return 2005	rr_AnnualReturn2005	1.62%
Annual Return 2006	rr_AnnualReturn2006	2.65%
Annual Return 2007	rr_AnnualReturn2007	2.87%
Annual Return 2008	rr_AnnualReturn2008	1.62%
Annual Return 2009	rr_AnnualReturn2009	0.19%
Annual Return 2010	rr_AnnualReturn2010	0.06%
Annual Return 2011	rr_AnnualReturn2011	0.05%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's Class C total return (pre-tax) from January 1, 2012 to September 30, 2012
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	0.01%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2007
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	0.74%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2010
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	0.01%
Label	rr_AverageAnnualReturnLabel	Class C Shares
1 Year	rr_AverageAnnualReturnYear01	0.05%
5 Years	rr_AverageAnnualReturnYear05	0.95%
10 Years	rr_AverageAnnualReturnYear10	1.06%
Since Inception	rr_AverageAnnualReturnSinceInception	1.75%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 11, 1995