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Risk/Return: rr_RiskReturnAbstract  
Registrant Name dei_EntityRegistrantName T. Rowe Price Short-Term Bond Fund, Inc.
Prospectus Date rr_ProspectusDate Oct. 01, 2014
Investor Class | T. Rowe Price Short-Term Bond Fund, Inc.
  
Risk/Return: rr_RiskReturnAbstract  
Risk/Return [Heading] rr_RiskReturnHeading T. Rowe Price

Short-Term Bond Fund

SUMMARY
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock The fund seeks a high level of income consistent with minimal fluctuation in principal value and liquidity.
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 shares of the fund.
Shareholder Fees Caption [Text] rr_ShareholderFeesCaption Fees and Expenses of the Fund

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 45.9% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 45.90%
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. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading] rr_StrategyHeading Investments, Risks, and Performance

Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock The fund will invest in a diversified portfolio of short- and intermediate-term investment-grade corporate, government, and mortgage-backed securities. The fund may also invest in money market securities, bank obligations, collateralized mortgage obligations, and foreign securities. Normally, the fund will invest at least 80% of its net assets (including any borrowings for investment purposes) in bonds. The fund’s average effective maturity will normally not exceed three years. The fund will only purchase securities that are rated within one of the four highest credit categories (AAA, AA, A, BBB, or equivalent) at the time of purchase by at least one major credit rating agency or, if unrated, deemed to be of comparable quality by T. Rowe Price. The fund may continue to hold a security that has been downgraded after purchase.

Investment decisions reflect the portfolio manager’s outlook for interest rates and the economy, as well as the prices, yields, and credit quality of various securities in which the fund may invest. For example, if interest rates are expected to fall, the fund may purchase longer-term securities (to the extent consistent with the fund’s investment program) in an attempt to seek higher yields and/or capital appreciation. Conversely, if interest rates are expected to rise, the fund may seek securities with shorter maturities.

The fund may sell holdings for a variety of reasons, such as to adjust the portfolio’s average maturity, duration, or credit quality or to shift assets into and out of higher-yielding or lower-yielding securities or different sectors.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock As with any mutual fund, there is no guarantee that the fund will achieve its objective. The fund’s share price fluctuates, which means you could lose money by investing in the fund. The principal risks of investing in this fund are summarized as follows:

Active management risk The fund is subject to the risk that the investment adviser’s judgments about the attractiveness, value, or potential appreciation of the fund’s investments may prove to be incorrect. If the securities selected and strategies employed by the fund fail to produce the intended results, the fund could underperform other funds with similar objectives and investment strategies.

Fixed income markets risk Economic and other market developments can adversely affect fixed income securities markets in the U.S. and abroad. At times, participants in these markets may develop concerns about the ability of certain issuers of debt securities to make timely principal and interest payments, or they may develop concerns about the ability of financial institutions that make markets in certain debt securities to facilitate an orderly market. Those concerns could cause increased volatility and reduced liquidity in particular securities or in the overall fixed income markets and the related derivatives markets. A lack of liquidity or other adverse credit market conditions may hamper the fund’s ability to sell the debt securities in which it invests or to find and purchase suitable debt instruments.

Interest rate risk This is the risk that a rise in interest rates will cause the price of a fixed rate debt security to fall. Prices fall because the bonds and notes in the fund’s portfolio become less attractive to other investors when securities with higher yields become available. Generally, securities with longer maturities and funds with longer weighted average maturities carry greater interest rate risk. The fund may be subject to a greater risk of rising interest rates due to the current period of historically low rates and the effect of potential government fiscal policy initiatives and resulting market reaction to those initiatives. During periods of extremely low or negative interest rates, the fund may not be able to maintain a positive yield or yields on par with historical levels.

Credit risk This is the risk that an issuer of a debt security could suffer an adverse change in financial condition that results in a payment default, security downgrade, or inability to meet a financial obligation. Although bonds and other debt securities rated BBB (or an equivalent rating) are considered investment-grade, they may still have speculative characteristics because their issuers are more vulnerable to financial setbacks and economic pressures than higher rated investment-grade securities.

Liquidity risk This is the risk that the fund may not be able to sell a holding in a timely manner at a desired price. Reduced liquidity in the bond markets can result from a number of events, such as significant trading activity, reductions in bond inventory, and rapid or unexpected changes in interest rates. Less liquid markets could lead to greater price volatility and limit the fund’s ability to sell a holding at a suitable price.

Foreign investing risk This is the risk that the fund’s investments in foreign securities may be adversely affected by political, social, and economic conditions overseas, greater volatility, reduced liquidity, or decreases in foreign currency values relative to the U.S. dollar.

Prepayment risk and extension risk Prepayment risk is the risk that the principal on mortgage-backed securities, other asset-backed securities or any debt security with an embedded call option may be prepaid at any time, which could reduce yield and market value. The rate of prepayments tends to increase as interest rates fall, which could cause the average maturity of the portfolio to shorten. Extension risk may result from a rise in interest rates, which tends to make mortgage-backed securities, asset-backed securities, and other callable debt securities more volatile.
Risk Lose Money [Text] rr_RiskLoseMoney The fund’s share price fluctuates, which means you could lose money by investing in the fund.
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading Performance
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock The bar chart showing calendar year returns and the average annual total returns table indicate risk by illustrating how much returns can differ from one year to the next and how fund performance compares with that of a comparable market index. The fund’s past performance (before and after taxes) is not necessarily an indication of future performance.

The fund can also experience short-term performance swings, as shown by the best and worst calendar quarter returns during the years depicted.
Performance Information Illustrates Variability of Returns [Text] rr_PerformanceInformationIllustratesVariabilityOfReturns The bar chart showing calendar year returns and the average annual total returns table indicate risk by illustrating how much returns can differ from one year to the next and how fund performance compares with that of a comparable market index.
Performance Availability Phone [Text] rr_PerformanceAvailabilityPhone 1-800-225-5132
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress troweprice.com
Performance Past Does Not Indicate Future [Text] rr_PerformancePastDoesNotIndicateFuture The fund’s past performance (before and after taxes) is not necessarily an indication of future performance.
Bar Chart [Heading] rr_BarChartHeading Short-Term Bond Fund
Calendar Year Returns
Bar Chart Closing [Text Block] rr_BarChartClosingTextBlock
  Quarter
 Ended		  Total
Return
Best Quarter   6/30/09  2.87%
Worst Quarter   6/30/04 -1.20%

The fund’s return for the six months ended 6/30/14 was 0.96%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns

Periods ended
December 31, 2013
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 Actual after-tax returns depend on an investor’s 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 a 401(k) account or individual retirement account.
Performance Table Explanation after Tax Higher rr_PerformanceTableExplanationAfterTaxHigher In some cases, the figure shown under “returns after taxes on distributions and sale of fund shares” may be higher than the figure shown under “returns before taxes” because the calculations assume the investor received a tax deduction for any loss incurred on the sale of shares.
Performance Table Narrative rr_PerformanceTableNarrativeTextBlock In addition, the average annual total returns table shows hypothetical after-tax returns to suggest how taxes paid by a shareholder may influence returns. 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. Actual after-tax returns depend on an investor’s 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 a 401(k) account or individual retirement account. In some cases, the figure shown under “returns after taxes on distributions and sale of fund shares” may be higher than the figure shown under “returns before taxes” because the calculations assume the investor received a tax deduction for any loss incurred on the sale of shares.
Performance Table Closing [Text Block] rr_PerformanceTableClosingTextBlock Updated performance information is available through troweprice.com or may be obtained by calling 1-800-225-5132.
Investor Class | T. Rowe Price Short-Term Bond Fund, Inc. | T. Rowe Price Short-Term Bond Fund, Inc.
  
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum deferred sales charge (load) rr_MaximumDeferredSalesChargeOverOther none
Redemption fee rr_RedemptionFeeOverRedemption none
Maximum account fee rr_MaximumAccountFee $ 20 [1]
Management fees rr_ManagementFeesOverAssets 0.39%
Distribution and service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.13%
Total annual fund operating expenses rr_ExpensesOverAssets 0.52%
1 year rr_ExpenseExampleYear01 53
3 years rr_ExpenseExampleYear03 167
5 years rr_ExpenseExampleYear05 291
10 years rr_ExpenseExampleYear10 $ 653
2004 rr_AnnualReturn2004 1.49%
2005 rr_AnnualReturn2005 1.74%
2006 rr_AnnualReturn2006 4.38%
2007 rr_AnnualReturn2007 5.48%
2008 rr_AnnualReturn2008 1.23%
2009 rr_AnnualReturn2009 9.00%
2010 rr_AnnualReturn2010 3.13%
2011 rr_AnnualReturn2011 1.46%
2012 rr_AnnualReturn2012 2.86%
2013 rr_AnnualReturn2013 0.30%
Year to Date Return, Label rr_YearToDateReturnLabel The fund's return for the six months ended
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2014
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn 0.96%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Best Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Jun. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 2.87%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Worst Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Jun. 30, 2004
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (1.20%)
1 Year rr_AverageAnnualReturnYear01 0.30%
5 Years rr_AverageAnnualReturnYear05 3.31%
10 Years rr_AverageAnnualReturnYear10 3.08%
Investor Class | T. Rowe Price Short-Term Bond Fund, Inc. | Returns after taxes on distributions | T. Rowe Price Short-Term Bond Fund, Inc.
  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 (0.37%)
5 Years rr_AverageAnnualReturnYear05 2.42%
10 Years rr_AverageAnnualReturnYear10 2.10%
Investor Class | T. Rowe Price Short-Term Bond Fund, Inc. | Returns after taxes on distributions and sale of fund shares | T. Rowe Price Short-Term Bond Fund, Inc.
  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 0.17%
5 Years rr_AverageAnnualReturnYear05 2.23%
10 Years rr_AverageAnnualReturnYear10 2.11%
Investor Class | T. Rowe Price Short-Term Bond Fund, Inc. | Barclays 1-3 Year U.S. Government/Credit Bond Index (reflects no deduction for fees, expenses, or taxes)
  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 0.64%
5 Years rr_AverageAnnualReturnYear05 2.02%
10 Years rr_AverageAnnualReturnYear10 2.91%
Investor Class | T. Rowe Price Short-Term Bond Fund, Inc. | Lipper Short Investment Grade Debt Funds Average
  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 0.55%
5 Years rr_AverageAnnualReturnYear05 3.61%
10 Years rr_AverageAnnualReturnYear10 2.73%
[1] Subject to certain exceptions, accounts with a balance of less than $10,000 are charged an annual $20 fee.