485BPOS

Filed with the U.S. Securities and Exchange Commission on March 8, 2019

1933 Act Registration File No. 333-179562

1940 Act File No. 811-22668

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

FORM N‑1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933	☒
Pre‑Effective Amendment No.	☐
Post‑Effective Amendment No. 467	☒
and
REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940	☒
Amendment No. 468	☒

(Check appropriate box or boxes.)

ETF SERIES SOLUTIONS

(Exact Name of Registrant as Specified in Charter)

615 East Michigan Street, Milwaukee, Wisconsin 53202

(Address of Principal Executive Offices, Zip Code)

 (Registrant’s Telephone Number, including Area Code): (414) 765-5586

Michael D. Barolsky, Vice President and Secretary

ETF Series Solutions

c/o U.S. Bancorp Fund Services, LLC

777 East Wisconsin Avenue, 10th Floor

Milwaukee, Wisconsin 53202

(Name and Address of Agent for Service)

Copy to:

W. John McGuire

Morgan, Lewis & Bockius LLP

1111 Pennsylvania Avenue, NW

Washington, DC 20004-2541

As soon as practical after the effective date of this Registration Statement

Approximate Date of Proposed Public Offering

It is proposed that this filing will become effective

☒	immediately upon filing pursuant to paragraph (b)
☐	on pursuant to paragraph (b)
☐	60 days after filing pursuant to paragraph (a)(1)
☐	on pursuant to paragraph (a)(1)
☐	75 days after filing pursuant to paragraph (a)(2)
☐	on pursuant to paragraph (a)(2) of Rule 485.

This Post-Effective Amendment (“PEA”) No. 467 to the Trust’s Registration Statement on Form N-1A hereby incorporates Parts A, B and C from the Trust’s Post-Effective Amendment No. 459 on Form N‑1A filed February 28, 2019.  This PEA No. 467 is filed for the sole purpose of submitting the XBRL exhibit for the risk/return summary first provided in Post-Effective Amendment No. 459 to the Trust’s Registration Statement.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933 and the Investment Company Act of 1940, the Registrant certifies that it meets all of the requirements for effectiveness of this Post-Effective Amendment (this “Amendment”) to its Registration Statement on Form N-1A under rule 485(b) under the Securities Act and has duly caused this Amendment to be signed below on its behalf by the undersigned, duly authorized, in the City of Milwaukee, State of Wisconsin, on March 8, 2019.

ETF Series Solutions

By: /s/ Michael D. Barolsky                  

Michael D. Barolsky

Vice President and Secretary

Pursuant to the requirements of the Securities Act of 1933, this Amendment has been signed below by the following persons in the capacities indicated on March 8, 2019.

Signature	Title
*/s/ David A. Massart	Trustee
David A. Massart
*/s/ Janet D. Olsen	Trustee
Janet D. Olsen
*/s/ Leonard M. Rush	Trustee
Leonard M. Rush
*/s/ Michael A. Castino	Trustee
Michael A. Castino
*/s/ Kristina R. Nelson	President
Kristina R. Nelson
*/s/ Kristen M. Weitzel	Treasurer
Kristen M. Weitzel

*By:  /s/ Michael D. Barolsky      

Michael D. Barolsky, Attorney-in-Fact

pursuant to Powers of Attorney

EXHIBIT INDEX

Exhibit	Exhibit No.
Instance Document	EX-101.INS
Schema Document	EX-101.SCH
Calculation Linkbase Document	EX-101.CAL
Definition Linkbase Document	EX-101.DEF
Label Linkbase Document	EX-101.LAB
Presentation Linkbase Document	EX-101.PRE

XML

Document and Entity Information	Total
Prospectus:
Document Type	485BPOS
Document Period End Date	Oct. 31, 2018
Registrant Name	ETF Series Solutions
Central Index Key	0001540305
Amendment Flag	false
Document Creation Date	Feb. 28, 2019
Document Effective Date	Feb. 28, 2019
Prospectus Date	Feb. 28, 2019
AAM S&P 500 High Dividend Value ETF | AAM S&P 500 High Dividend Value ETF
Prospectus:
Trading Symbol	SPDV
AAM S&P Emerging Markets High Dividend Value ETF | AAM S&P Emerging Markets High Dividend Value ETF
Prospectus:
Trading Symbol	EEMD

XML

AAM S&P 500 High Dividend Value ETF

AAM S&P 500 High Dividend Value ETF

Investment Objective

The AAM S&P 500 High Dividend Value ETF (the “Fund”) seeks to track the total return performance, before fees and expenses, of the S&P 500 Dividend and Free Cash Flow Yield Index (the “Index”).

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund (“Shares”). This table and the Example below do not include the brokerage commissions that investors may pay on their purchases and sales of Shares.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	AAM S&P 500 High Dividend Value ETF AAM S&P 500 High Dividend Value ETF
Management Fees	0.29%
Distribution and Service (Rule 12b-1) Fees	none
Other Expenses	none
Total Annual Fund Operating Expenses	0.29%

Expense Example

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other 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	1 Year	3 Years	5 Years	10 Years
AAM S&P 500 High Dividend Value ETF | AAM S&P 500 High Dividend Value ETF | USD ($)	30	93	163	368

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 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. For the fiscal period November 28, 2017 (commencement of operations) through October 31, 2018, the Fund’s portfolio turnover rate was 38% of the average value of its portfolio.

Principal Investment Strategies

The Fund uses a “passive management” (or indexing) approach to track the total return performance, before fees and expenses, of the Index.

S&P 500 Dividend and Free Cash Flow Yield Index

The Index is a rules-based, equal-weighted index that is designed to provide exposure to the constituents of the S&P 500® Index that exhibit both high dividend yield and sustainable dividend distribution characteristics, while maintaining diversified sector exposure. The Index was developed in 2017 by S&P Dow Jones Indices, a division of S&P Global. The S&P 500 Index consists of approximately 500 leading U.S.-listed companies representing approximately 80% of the U.S. equity market capitalization.

Construction of the Index begins with the universe of equity securities that are included in the S&P 500 Index. For each equity security in the S&P 500 Index, the security’s dividend yield and free-cash-flow yield (i.e., a company’s cash flow from operations less capital expenditures divided by its market capitalization) are adjusted to account for outliers. If a security’s dividend yield or free-cash-flow yield is in the top or bottom 2.5% of the S&P 500 Index, the dividend yield or free-cash-flow yield, as applicable, for such security is replaced with the dividend yield or free-cash-flow yield of the security nearest to such top or bottom 2.5% threshold. The universe is then screened to keep only equity securities with a positive indicated annual dividend yield (i.e., yield based on a company’s most recent dividend amount) and free-cash-flow yield. The remaining securities are referred to as the “Selection Pool”.

For each security in the Selection Pool, the security’s dividend yield and free-cash-flow yield are then scored using a statistical normalization model (i.e., a tool to compare how close each yield is to the average yield for the Selection Pool) to assign a dividend yield score and free-cash-flow yield score from zero to one for each company. The equity securities in the Selection Pool are then ranked by the product of their dividend yield score and free-cash-flow yield score, and the top five scoring securities are selected from each sector (collectively, the “Index Constituents”). The Index uses Standard & Poor’s Global Industry Classification Standards to define companies within one of the following sectors: consumer discretionary, consumer staples, energy, financials, health care, industrials, information technology, materials, real estate, communication services, and utilities. Fewer than five securities may be selected if there are fewer than five securities in the Selection Pool for a given sector.

The Index is reconstituted (i.e., Index Constituents are added or deleted and weights are reset to equal-weight) semi-annually after the close of the last business day in January and July. At the time of each reconstitution of the Index, Index Constituents are added or deleted based on company data as of the last business day of December and June, respectively, and the Index Constituents are equally-weighted based on closing prices as of five business days prior to the last business day of the reconstitution month. If an Index Constituent is removed from the S&P 500 Index, such security will simultaneously be removed from the Index. Additions to the Index Constituents only take place during the semi-annual reconstitutions.

The Fund’s Investment Strategy

The Fund attempts to invest all, or substantially all, of its assets in the component securities that make up the Index. Under normal circumstances, at least 80% of the Fund’s total assets (exclusive of any collateral held from securities lending) will be invested in the component securities of the Index. The Fund’s investment adviser expects that, over time, the correlation between the Fund’s performance and that of the Index, before fees and expenses, will be 95% or better.

The Fund will generally use a “replication” strategy to achieve its investment objective, meaning the Fund generally will invest in all of the component securities of the Index in approximately the same proportion as in the Index. However, the Fund may use a “representative sampling” strategy, meaning it may invest in a sample of the securities in the Index whose risk, return, and other characteristics closely resemble the risk, return, and other characteristics of the Index as a whole, when the Fund’s sub-adviser believes it is in the best interests of the Fund (e.g., when replicating the Index involves practical difficulties or substantial costs, an Index constituent becomes temporarily illiquid, unavailable, or less liquid, or as a result of legal restrictions or limitations that apply to the Fund but not to the Index).

The Fund generally may invest up to 20% of its total assets (exclusive of any collateral held from securities lending) in securities or other investments not included in the Index, but which the Fund’s sub-adviser believes will help the Fund track the Index. For example, the Fund may invest in securities that are not components of the Index to reflect various corporate actions and other changes to the Index (such as reconstitutions, additions, and deletions).

To the extent the Index concentrates (i.e., holds more than 25% of its total assets) in the securities of a particular industry or group of related industries, the Fund will concentrate its investments to approximately the same extent as the Index.

Principal Investment Risks

The principal risks of investing in the Fund are summarized below. As with any investment, there is a risk that you could lose all or a portion of your investment in the Fund. The following riskscould affect the value of your investmentin the Fund:

· Equity Market Risk. The equity securities held in the Fund’s portfolio may experience sudden, unpredictable drops in value or long periods of decline in value. This may occur because of factors that affect securities markets generally or factors affecting specific issuers, industries, or sectors in which the Fund invests. Common stocks are generally exposed to greater risk than other types of securities, such as preferred stocks and debt obligations, because common stockholders generally have inferior rights to receive payment from issuers.

· High Dividend Investing Risk. Companies with a high yield or payout ratio may reduce their dividend or stop paying dividends entirely while they are included in the Index. Such events could lower the price or yield of such company’s equity securities. Additionally, equity securities with a high yield or payout ratio may underperform other securities in certain market conditions.

· Limited Operating History Risk. The Fund is a recently organized, diversified management investment company with a limited operating history. As a result, prospective investors have a limited track record or history on which to base their investment decision.

· Market Risk. The trading prices of equity securities and other instruments fluctuate in response to a variety of factors. The Fund’s net asset value (“NAV”) and market price may fluctuate significantly in response to these and other factors. As a result, an investor could lose money over short or long periods of time.

· Passive Investment Risk. The Fund is not actively managed and its sub-adviser would not sell shares of an equity security due to current or projected underperformance of a security, industry, or sector, unless that security is removed from the Index or the selling of shares of that security is otherwise required upon a reconstitution of the Index as addressed in the Index methodology.

· Shares May Trade at Prices Other Than NAV. As with all ETFs, Shares may be bought and sold in the secondary market at market prices. Although it is expected that the market price of Shares will approximate the Fund’s NAV, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount) due to supply and demand of Shares or during periods of market volatility. This risk is heightened in times of market volatility, periods of steep market declines, and periods when there is limited trading activity for Shares in the secondary market, in which case such premiums or discounts may be significant.

· Tracking Error Risk. As with all index funds, the performance of the Fund and its Index may differ from each other for a variety of reasons. For example, the Fund incurs operating expenses and portfolio transaction costs not incurred by the Index. In addition, the Fund may not be fully invested in the securities of the Index at all times or may hold securities not included in the Index.

Performance

The following performance information indicates some of the risks of investing in the Fund. The bar chart shows the Fund’s performance for the calendar year ended December 31, 2018. The table illustrates how the Fund’s average annual returns for the 1‑year and since inception periods compare with those of a broad measure of market performance and the Index. The Fund’s past performance, before and after taxes, does not necessarily indicate how it will perform in the future. Updated performance information is also available on the Fund’s website at www.aamlive.com.

Calendar Year Total Return

During the period of time shown in the bar chart, the Fund’s highest quarterly return was 3.97% for the quarter ended September 30, 2018 and the lowest quarterly return was -12.71% for the quarter ended December 31, 2018.

Average Annual Total Returns For the Periods Ended December 31, 2018

Average Annual Returns - AAM S&P 500 High Dividend Value ETF	Label	Average Annual Returns, 1 Year	Average Annual Returns, Since Inception	Average Annual Returns, Inception Date
AAM S&P 500 High Dividend Value ETF	Return Before Taxes	(6.13%)	(1.78%)	Nov. 28, 2017
After Taxes on Distributions | AAM S&P 500 High Dividend Value ETF	Return After Taxes on Distributions	(6.92%)	(2.60%)
After Taxes on Distributions and Sale of Fund Shares | AAM S&P 500 High Dividend Value ETF	Return After Taxes on Distributions and Sale of Fund Shares	(3.08%)	(1.33%)
S&P 500 Dividend and Free Cash Flow Yield Index (reflects no deduction for fees, expenses, or taxes)	S&P 500 Dividend and Free Cash Flow Yield Index (reflects no deduction for fees, expenses, or taxes)	(5.85%)	(1.50%)	Nov. 28, 2017
S&P 500® Index (reflects no deduction for fees, expenses, or taxes)	S&P 500® Index (reflects no deduction for fees, expenses, or taxes)	(4.38%)	(2.31%)	Nov. 28, 2017

After-tax returns are calculated using the historical highest individual federal marginal income tax rates during the period covered by the table above 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. In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures for the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as an individual retirement account (“IRA”) or other tax-advantaged accounts.

XML

Label

Element

Value

AAM S&P 500 High Dividend Value ETF

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

AAM S&P 500 High Dividend Value ETF

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The AAM S&P 500 High Dividend Value ETF (the “Fund”) seeks to track the total return performance, before fees and expenses, of the S&P 500 Dividend and Free Cash Flow Yield Index (the “Index”).

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses of the Fund

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 (“Shares”). This table and the Example below do not include the brokerage commissions that investors may pay on their purchases and sales of 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)

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 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. For the fiscal period November 28, 2017 (commencement of operations) through October 31, 2018, the Fund’s portfolio turnover rate was 38% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

38.00%

Expense Exchange Traded Fund Commissions [Text]

rr_ExpenseExchangeTradedFundCommissions

This table and the Example below do not include the brokerage commissions that investors may pay on their purchases and sales of Shares.

Expense Example [Heading]

rr_ExpenseExampleHeading

Expense 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 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 Fund uses a “passive management” (or indexing) approach to track the total return performance, before fees and expenses, of the Index.

S&P 500 Dividend and Free Cash Flow Yield Index

The Index is a rules-based, equal-weighted index that is designed to provide exposure to the constituents of the S&P 500® Index that exhibit both high dividend yield and sustainable dividend distribution characteristics, while maintaining diversified sector exposure. The Index was developed in 2017 by S&P Dow Jones Indices, a division of S&P Global. The S&P 500 Index consists of approximately 500 leading U.S.-listed companies representing approximately 80% of the U.S. equity market capitalization.

Construction of the Index begins with the universe of equity securities that are included in the S&P 500 Index. For each equity security in the S&P 500 Index, the security’s dividend yield and free-cash-flow yield (i.e., a company’s cash flow from operations less capital expenditures divided by its market capitalization) are adjusted to account for outliers. If a security’s dividend yield or free-cash-flow yield is in the top or bottom 2.5% of the S&P 500 Index, the dividend yield or free-cash-flow yield, as applicable, for such security is replaced with the dividend yield or free-cash-flow yield of the security nearest to such top or bottom 2.5% threshold. The universe is then screened to keep only equity securities with a positive indicated annual dividend yield (i.e., yield based on a company’s most recent dividend amount) and free-cash-flow yield. The remaining securities are referred to as the “Selection Pool”.

For each security in the Selection Pool, the security’s dividend yield and free-cash-flow yield are then scored using a statistical normalization model (i.e., a tool to compare how close each yield is to the average yield for the Selection Pool) to assign a dividend yield score and free-cash-flow yield score from zero to one for each company. The equity securities in the Selection Pool are then ranked by the product of their dividend yield score and free-cash-flow yield score, and the top five scoring securities are selected from each sector (collectively, the “Index Constituents”). The Index uses Standard & Poor’s Global Industry Classification Standards to define companies within one of the following sectors: consumer discretionary, consumer staples, energy, financials, health care, industrials, information technology, materials, real estate, communication services, and utilities. Fewer than five securities may be selected if there are fewer than five securities in the Selection Pool for a given sector.

The Index is reconstituted (i.e., Index Constituents are added or deleted and weights are reset to equal-weight) semi-annually after the close of the last business day in January and July. At the time of each reconstitution of the Index, Index Constituents are added or deleted based on company data as of the last business day of December and June, respectively, and the Index Constituents are equally-weighted based on closing prices as of five business days prior to the last business day of the reconstitution month. If an Index Constituent is removed from the S&P 500 Index, such security will simultaneously be removed from the Index. Additions to the Index Constituents only take place during the semi-annual reconstitutions.

The Fund’s Investment Strategy

The Fund attempts to invest all, or substantially all, of its assets in the component securities that make up the Index. Under normal circumstances, at least 80% of the Fund’s total assets (exclusive of any collateral held from securities lending) will be invested in the component securities of the Index. The Fund’s investment adviser expects that, over time, the correlation between the Fund’s performance and that of the Index, before fees and expenses, will be 95% or better.

The Fund will generally use a “replication” strategy to achieve its investment objective, meaning the Fund generally will invest in all of the component securities of the Index in approximately the same proportion as in the Index. However, the Fund may use a “representative sampling” strategy, meaning it may invest in a sample of the securities in the Index whose risk, return, and other characteristics closely resemble the risk, return, and other characteristics of the Index as a whole, when the Fund’s sub-adviser believes it is in the best interests of the Fund (e.g., when replicating the Index involves practical difficulties or substantial costs, an Index constituent becomes temporarily illiquid, unavailable, or less liquid, or as a result of legal restrictions or limitations that apply to the Fund but not to the Index).

The Fund generally may invest up to 20% of its total assets (exclusive of any collateral held from securities lending) in securities or other investments not included in the Index, but which the Fund’s sub-adviser believes will help the Fund track the Index. For example, the Fund may invest in securities that are not components of the Index to reflect various corporate actions and other changes to the Index (such as reconstitutions, additions, and deletions).

To the extent the Index concentrates (i.e., holds more than 25% of its total assets) in the securities of a particular industry or group of related industries, the Fund will concentrate its investments to approximately the same extent as the Index.

Risk [Heading]

rr_RiskHeading

Principal Investment Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

The principal risks of investing in the Fund are summarized below. As with any investment, there is a risk that you could lose all or a portion of your investment in the Fund. The following riskscould affect the value of your investmentin the Fund:

· Equity Market Risk. The equity securities held in the Fund’s portfolio may experience sudden, unpredictable drops in value or long periods of decline in value. This may occur because of factors that affect securities markets generally or factors affecting specific issuers, industries, or sectors in which the Fund invests. Common stocks are generally exposed to greater risk than other types of securities, such as preferred stocks and debt obligations, because common stockholders generally have inferior rights to receive payment from issuers.

· High Dividend Investing Risk. Companies with a high yield or payout ratio may reduce their dividend or stop paying dividends entirely while they are included in the Index. Such events could lower the price or yield of such company’s equity securities. Additionally, equity securities with a high yield or payout ratio may underperform other securities in certain market conditions.

· Limited Operating History Risk. The Fund is a recently organized, diversified management investment company with a limited operating history. As a result, prospective investors have a limited track record or history on which to base their investment decision.

· Market Risk. The trading prices of equity securities and other instruments fluctuate in response to a variety of factors. The Fund’s net asset value (“NAV”) and market price may fluctuate significantly in response to these and other factors. As a result, an investor could lose money over short or long periods of time.

· Passive Investment Risk. The Fund is not actively managed and its sub-adviser would not sell shares of an equity security due to current or projected underperformance of a security, industry, or sector, unless that security is removed from the Index or the selling of shares of that security is otherwise required upon a reconstitution of the Index as addressed in the Index methodology.

· Shares May Trade at Prices Other Than NAV. As with all ETFs, Shares may be bought and sold in the secondary market at market prices. Although it is expected that the market price of Shares will approximate the Fund’s NAV, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount) due to supply and demand of Shares or during periods of market volatility. This risk is heightened in times of market volatility, periods of steep market declines, and periods when there is limited trading activity for Shares in the secondary market, in which case such premiums or discounts may be significant.

· Tracking Error Risk. As with all index funds, the performance of the Fund and its Index may differ from each other for a variety of reasons. For example, the Fund incurs operating expenses and portfolio transaction costs not incurred by the Index. In addition, the Fund may not be fully invested in the securities of the Index at all times or may hold securities not included in the Index.

Risk Lose Money [Text]

rr_RiskLoseMoney

As with any investment, there is a risk that you could lose all or a portion of your investment in the Fund.

Bar Chart and Performance Table [Heading]

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Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following performance information indicates some of the risks of investing in the Fund. The bar chart shows the Fund’s performance for the calendar year ended December 31, 2018. The table illustrates how the Fund’s average annual returns for the 1‑year and since inception periods compare with those of a broad measure of market performance and the Index. The Fund’s past performance, before and after taxes, does not necessarily indicate how it will perform in the future. Updated performance information is also available on the Fund’s website at www.aamlive.com.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following performance information indicates some of the risks of investing in the Fund.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

www.aamlive.com

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The Fund’s past performance, before and after taxes, does not necessarily indicate how it will perform in the future.

Bar Chart [Heading]

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Calendar Year Total Return

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the period of time shown in the bar chart, the Fund’s highest quarterly return was 3.97% for the quarter ended September 30, 2018 and the lowest quarterly return was -12.71% for the quarter ended December 31, 2018.

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

highest quarterly return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2018

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

3.97%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

lowest quarterly return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(12.71%)

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 during the period covered by the table above and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as an individual retirement account (“IRA”) or other tax-advantaged accounts.

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures for the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates during the period covered by the table above 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. In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures for the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as an individual retirement account (“IRA”) or other tax-advantaged accounts.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns For the Periods Ended December 31, 2018

AAM S&P 500 High Dividend Value ETF | S&P 500 Dividend and Free Cash Flow Yield Index (reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

S&P 500 Dividend and Free Cash Flow Yield Index (reflects no deduction for fees, expenses, or taxes)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(5.85%)

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

(1.50%)

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2017

AAM S&P 500 High Dividend Value ETF | S&P 500® Index (reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

S&P 500® Index (reflects no deduction for fees, expenses, or taxes)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(4.38%)

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

(2.31%)

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2017

AAM S&P 500 High Dividend Value ETF | AAM S&P 500 High Dividend Value ETF

Risk/Return:

rr_RiskReturnAbstract

Management Fees

rr_ManagementFeesOverAssets

0.29%

Distribution and Service (Rule 12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

none

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.29%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 30

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

93

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

163

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

$ 368

Annual Return 2018

rr_AnnualReturn2018

(6.13%)

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(6.13%)

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

(1.78%)

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2017

AAM S&P 500 High Dividend Value ETF | AAM S&P 500 High Dividend Value ETF | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(6.92%)

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

(2.60%)

AAM S&P 500 High Dividend Value ETF | AAM S&P 500 High Dividend Value ETF | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(3.08%)

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

(1.33%)

XML

AAM S&P Emerging Markets High Dividend Value ETF

AAM S&P Emerging Markets High Dividend Value ETF

Investment Objective

The AAM S&P Emerging Markets High Dividend Value ETF (the “Fund”) seeks to track the total return performance, before fees and expenses, of the S&P Emerging Markets Dividend and Free Cash Flow Yield Index (the “Index”).

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund (“Shares”). This table and the Example below do not include the brokerage commissions that investors may pay on their purchases and sales of Shares.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	AAM S&P Emerging Markets High Dividend Value ETF AAM S&P Emerging Markets High Dividend Value ETF
Management Fees	0.49%
Distribution and Service (Rule 12b-1) Fees	none
Other Expenses	none
Acquired Fund Fees and Expenses	0.01%	[1]
Total Annual Fund Operating Expenses	0.50%

Expense Example

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other 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	1 Year	3 Years	5 Years	10 Years
AAM S&P Emerging Markets High Dividend Value ETF | AAM S&P Emerging Markets High Dividend Value ETF | USD ($)	51	160	280	628

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 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. For the fiscal period November 28, 2017 (commencement of operations) through October 31, 2018, the Fund’s portfolio turnover rate was 104% of the average value of its portfolio.

Principal Investment Strategies

The Fund uses a “passive management” (or indexing) approach to track the total return performance, before fees and expenses, of the Index.

S&P Emerging Markets Dividend and Free Cash Flow Yield Index

The Index is a rules-based, equal-weighted index that is designed to provide exposure to the constituents of the S&P Emerging Plus LargeMidCap Index that exhibit both high dividend yield and sustainable dividend distribution characteristics, while maintaining diversified sector exposure. The Index was developed in 2017 by S&P Dow Jones Indices, a division of S&P Global. The S&P Emerging Plus LargeMidCap Index is designed to measure the performance of large- and mid-capitalization securities in emerging markets. The S&P Emerging Plus LargeMidCap Index includes equity securities that are listed in Brazil, Chile, China, Colombia, the Czech Republic, Egypt, Greece, Hungary, India, Indonesia, Malaysia, Mexico, Pakistan, Peru, the Philippines, Poland, Qatar, Russia, South Africa, South Korea, Taiwan, Thailand, Turkey, and the United Arab Emirates (collectively, the “Emerging Markets”).

Construction of the Index begins with the universe of equity securities that are included in the S&P Emerging Plus LargeMidCap Index, have a minimum float-adjusted market capitalization of US$300 million, and have a median daily traded value of at least US$1 million. For each equity security in the S&P Emerging Plus LargeMidCap Index, the security’s dividend yield and free-cash-flow yield (i.e., a company’s cash flow from operations less capital expenditures divided by its market capitalization) are then adjusted to account for outliers. If a security’s dividend yield or free-cash-flow yield is in the top or bottom 2.5% of the S&P Emerging Plus LargeMidCap Index, the dividend yield or free-cash-flow yield, as applicable, for such security is replaced with the dividend yield or free-cash-flow yield of the security nearest to such top or bottom 2.5% threshold. The universe is then screened to keep only equity securities with a positive realized dividend yield (i.e., yield based on the total dividends paid for the most recent 12-month period) and free-cash-flow yield. The remaining securities are referred to as the “Selection Pool”.

For each security in the Selection Pool, the security’s dividend yield or free-cash-flow yield are then scored using a statistical normalization model (i.e., a tool to compare how close each yield is to the average yield for the Selection Pool) to assign a dividend yield score and free-cash-flow yield score from zero to one for each company. The equity securities in the Selection Pool are then ranked by the product of their dividend yield score and free-cash-flow yield score, and the top five scoring securities are selected from each sector (collectively, the “Index Constituents”). The Index uses Standard & Poor’s Global Industry Classification Standards to define companies within one of the following sectors: consumer discretionary, consumer staples, energy, financials, health care, industrials, information technology, materials, real estate, communication services, and utilities. Fewer than five securities may be selected if there are fewer than five securities in the Selection Pool for a given sector.

The Index is reconstituted (i.e., Index Constituents are added or deleted and weights are reset to equal-weight) semi-annually after the close of the last business day in January and July. At the time of each reconstitution of the Index, Index Constituents are added or deleted based on company data as of the last business day of December and June, respectively, and the Index Constituents are equally-weighted based on closing prices as of five business days prior to the last business day of the reconstitution month. If an Index Constituent is removed from the S&P Emerging Plus LargeMidCap Index, such security will simultaneously be removed from the Index. Additions to the Index Constituents only take place during the semi-annual reconstitutions. If multiple share classes of a single company qualify for inclusion in the Index, only the share class with the highest liquidity, measured by median daily value traded, is selected. As of December 31, 2018, the Index included significant exposure to companies in China, Taiwan, Brazil, and Russia.

The Fund’s Investment Strategy

The Fund attempts to invest all, or substantially all, of its assets in the component securities that make up the Index. Under normal circumstances, at least 80% of the Fund’s total assets (exclusive of any collateral held from securities lending) will be invested in the component securities of the Index and depositary receipts representing Index components. The Fund’s investment adviser expects that, over time, the correlation between the Fund’s performance and that of the Index, before fees and expenses, will be 95% or better.

The Fund will generally use a “replication” strategy to achieve its investment objective, meaning the Fund generally will invest in all of the component securities of the Index in approximately the same proportion as in the Index. However, the Fund may use a “representative sampling” strategy, meaning it may invest in a sample of the securities in the Index whose risk, return, and other characteristics closely resemble the risk, return, and other characteristics of the Index as a whole, when the Fund’s sub-adviser believes it is in the best interests of the Fund (e.g., when replicating the Index involves practical difficulties or substantial costs, an Index constituent becomes temporarily illiquid, unavailable, or less liquid, or as a result of legal restrictions or limitations that apply to the Fund but not to the Index).

The Fund generally may invest up to 20% of its total assets (exclusive of any collateral held from securities lending) in securities or other investments not included in the Index, but which the Fund’s sub-adviser believes will help the Fund track the Index. For example, the Fund may invest in securities that are not components of the Index to reflect various corporate actions and other changes to the Index (such as reconstitutions, additions, and deletions).

To the extent the Index concentrates (i.e., holds more than 25% of its total assets) in the securities of a particular industry or group of related industries, the Fund will concentrate its investments to approximately the same extent as the Index.

Principal Investment Risks

The principal risks of investing in the Fund are summarized below. As with any investment, there is a risk that you could lose all or a portion of your investment in the Fund. The following riskscould affect the value of your investmentin the Fund:

· Capital Controls and Sanctions Risk. Economic conditions, such as volatile currency exchange rates and interest rates, political events, military action and other conditions may, without prior warning, lead to foreign government intervention (including intervention by the U.S. government with respect to foreign governments, economic sectors, foreign companies and related securities and interests) and the imposition of capital controls and/or sanctions, which may also include retaliatory actions of one government against another government, such as seizure of assets. Capital controls and/or sanctions include the prohibition of, or restrictions on, the ability to transfer currency, securities or other assets. Capital controls and/or sanctions may also impact the ability of the Fund to buy, sell or otherwise transfer securities or currency, negatively impact the value and/or liquidity of such instruments, adversely affect the trading market and price for shares of the Fund, and cause the Fund to decline in value.

· Currency Exchange Rate Risk. The Fund invests primarily in investments denominated in non-U.S. currencies or in securities that provide exposure to such currencies. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund’s investment and the value of your Shares. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money.

· Depositary Receipt Risk. Depositary Receipts involve risks similar to those associated with investments in foreign securities, such as changes in political or economic conditions of other countries and changes in the exchange rates of foreign currencies. Depositary Receipts listed on U.S. exchanges are issued by banks or trust companies, and entitle the holder to all dividends and capital gains that are paid out on the underlying foreign shares (“Underlying Shares”). When the Fund invests in Depositary Receipts as a substitute for an investment directly in the Underlying Shares, the Fund is exposed to the risk that the Depositary Receipts may not provide a return that corresponds precisely with that of the Underlying Shares.

· Equity Market Risk. The equity securities held in the Fund’s portfolio may experience sudden, unpredictable drops in value or long periods of decline in value. This may occur because of factors that affect securities markets generally or factors affecting specific issuers, industries, sectors or companies in which the Fund invests. Common stocks are generally exposed to greater risk than other types of securities, such as preferred stocks and debt obligations, because common stockholders generally have inferior rights to receive payment from issuers.

· Emerging Markets Risk. The Fund invests primarily in companies organized in emerging market nations. Investments in securities and instruments traded in developing or emerging markets, or that provide exposure to such securities or markets, can involve additional risks relating to political, economic, or regulatory conditions not associated with investments in U.S. securities and instruments or investments in more developed international markets. Such conditions may impact the ability of the Fund to buy, sell or otherwise transfer securities, adversely affect the trading market and price for Shares and cause the Fund to decline in value. Less information may be available about companies in emerging markets than in developed markets because such emerging markets companies may not subject to accounting, auditing and financial reporting standards or to other regulatory practices required by U.S. companies. 

· Foreign Securities Risk. Investments in non-U.S. securities involve certain risks that may not be present with investments in U.S. securities. For example, investments in non-U.S. securities may be subject to risk of loss due to foreign currency fluctuations or to political or economic instability. Investments in non-U.S. securities also may be subject to withholding or other taxes and may be subject to additional trading, settlement, custodial, and operational risks. These and other factors can make investments in the Fund more volatile and potentially less liquid than other types of investments.

· Geographic Investment Risk. To the extent the Fund invests a significant portion of its assets in the securities of companies of a single country or region, it is more likely to be impacted by events or conditions affecting that country or region.

o Risks of Investing in Brazil —Investments in securities of Brazilian companies are subject to regulatory and economic interventions that the Brazilian government has frequently exercised in the past, including the setting of wage and price controls, blocking access to bank accounts, imposing exchange controls and limiting imports. Investments are also subject to certain restrictions on foreign investment as provided by Brazilian law. The Brazilian economy has historically been subject to high rates of inflation and a high level of debt, all of which may stifle economic growth. Despite rapid development in recent years, Brazil still suffers from high levels of corruption, crime and income disparity. There is the possibility that such conditions may lead to social unrest and political upheaval in the future, which may have adverse effects on the Fund's investments.

o Risks of Investing in China — China may be subject to considerable degrees of economic, political and social instability. China is a developing market and demonstrates significantly higher volatility from time to time in comparison to developed markets. Over the past 25 years, the Chinese government has undertaken reform of economic and market practices and is expanding the sphere of private ownership of property in China. However, Chinese markets generally continue to experience inefficiency, volatility and pricing anomalies resulting from governmental influence, a lack of publicly available information and/or political and social instability. Internal social unrest or confrontations with other neighboring countries, including military conflicts in response to such events, may also disrupt economic development in China and result in a greater risk of currency fluctuations, currency convertibility, interest rate fluctuations and higher rates of inflation. Export growth continues to be a major driver of China’s rapid economic growth. Reduction in spending on Chinese products and services, institution of tariffs or other trade barriers, or a downturn in any of the economies of China’s key trading partners may have an adverse impact on the Chinese economy.

o Risks of Investing in Russia —Investment in securities of Russian issuers involves heightened risks not typically associated with investments in securities of issuers in more developed countries, including, among others, expropriation and/or nationalization of assets, restrictions on and government intervention in international trade, confiscatory or punitive taxation, regional conflict, political instability, including authoritarian and/or military involvement in governmental decision making, armed conflict, the imposition of economic sanctions by other nations, the impact on the economy as a result of civil unrest, and social instability as a result of religious, ethnic and/or socioeconomic unrest.

Securities markets in Russia are subject to greater risks associated with market volatility, lower market capitalization, lower trading volume, inflation, greater price fluctuations, uncertainty regarding the existence of trading markets, governmental control and heavy regulation of labor and industry.

The government in Russia may restrict or control to varying degrees the ability of foreign investors to invest in securities of issuers located or operating in Russia. These restrictions and/or controls may at times limit or prevent foreign investment in securities of issuers located or operating in Russia. Moreover, governmental approval or special licenses may be required prior to investments by foreign investors and may limit the amount of investments by foreign investors in a particular industry and/or issuer and may limit such foreign investment to a certain class of securities of an issuer that may have less advantageous rights than the classes available for purchase by domiciliaries of Russia and/or impose additional taxes on foreign investors.

Despite recent reform and privatization, the Russian government continues to control a large share of economic activity in the region. The Russian government owns shares in corporations in a range of sectors. Additionally, because Russia produces and exports large volumes of oil and gas, the Russian economy is particularly sensitive to the price of oil and gas on the world market, and a decline in the price of oil and gas could have a significant negative impact on the Russian economy. Current political and economic events in Russia and the effects of the recent global economic crisis on the Russian economy may have significant adverse effects on the Russian ruble and on the value and liquidity of the Fund’s investments.

o Risks of Investing in Taiwan — Taiwan is a small island state with few raw material resources and limited land area and is reliant on imports for its commodity needs. Any fluctuations or shortages in the commodity markets could have a negative impact on the Taiwanese economy. Also, continued labor outsourcing may adversely affect the Taiwanese economy. Taiwan’s economy is intricately linked with economies of Asian countries that have experienced over-extensions of credit, frequent and pronounced currency fluctuations, currency devaluations, currency repatriation, rising unemployment and fluctuations in inflation. The Taiwanese economy is dependent on the economies of Japan and China, as well as the United States, and negative changes in their economies or a reduction in purchases by any of them of Taiwanese products and services would likely have an adverse impact on the Taiwanese economy. Taiwan’s geographic proximity to China and Taiwan’s history of political contention with China have resulted in ongoing tensions with China, including the risk of war with China. These tensions may materially affect the Taiwanese economy and securities markets.

· Geopolitical Risk. Some countries and regions in which the Fund invests have experienced security concerns, war or threats of war and aggression, terrorism, economic uncertainty, natural and environmental disasters and/or systemic market dislocations that have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on the U.S. and world economies and markets generally, each of which may negatively impact the Fund’s investments.

· High Dividend Investing Risk. Companies with a high yield or payout ratio may reduce their dividend or stop paying dividends entirely while they are included in the Index. Such events could lower the price or yield of such company’s equity securities. Additionally, equity securities with a high yield or payout ratio may underperform other securities in certain market conditions.

· Limited Operating History Risk. The Fund is a recently organized, diversified management investment company with a limited operating history. As a result, prospective investors have a limited track record or history on which to base their investment decision.

· Market Risk. The trading prices of equity securities and other instruments fluctuate in response to a variety of factors. The Fund’s net asset value (“NAV”) and market price may fluctuate significantly in response to these and other factors. As a result, an investor could lose money over short or long periods of time.

· Passive Investment Risk. The Fund is not actively managed and its sub-adviser would not sell shares of an equity security due to current or projected underperformance of a security, industry or sector, unless that security is removed from the Index or the selling of shares of that security is otherwise required upon a rebalancing of the Index as addressed in the Index methodology.

· Portfolio Turnover Risk. The Fund may trade all or a significant portion of the securities in its portfolio in connection with each rebalance and reconstitution of its Index. A high portfolio turnover rate increases transaction costs, which may increase the Fund’s expenses. Frequent trading may also cause adverse tax consequences for investors in the Fund due to an increase in short-term capital gains.

· Shares May Trade at Prices Other Than NAV. As with all ETFs, Shares may be bought and sold in the secondary market at market prices. Although it is expected that the market price of Shares will approximate the Fund’s NAV, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount) due to supply and demand of Shares or during periods of market volatility. This risk is heightened in times of market volatility, periods of steep market declines, and periods when there is limited trading activity for Shares in the secondary market, in which case such premiums or discounts may be significant. Because securities held by the Fund trade on foreign exchanges that are closed when the Fund’s primary listing exchange is open, the Fund is likely to experience premiums and discounts greater than those of domestic ETFs.

· Smaller Companies Risk. The equity securities of smaller companies have historically been subject to greater investment risk than securities of larger companies. The prices of equity securities of smaller companies tend to be more volatile and less liquid than the prices of equity securities of larger companies.

· Tracking Error Risk. As with all index funds, the performance of the Fund and its Index may differ from each other for a variety of reasons. For example, the Fund incurs operating expenses and portfolio transaction costs not incurred by the Index. In addition, the Fund may not be fully invested in the securities of the Index at all times or may hold securities not included in the Index.

Performance

The following performance information indicates some of the risks of investing in the Fund. The bar chart shows the Fund’s performance for the calendar year ended December 31, 2018. The table illustrates how the Fund’s average annual returns for the 1‑year and since inception periods compare with those of a broad measure of market performance and the Index. The Fund’s past performance, before and after taxes, does not necessarily indicate how it will perform in the future. Updated performance information is also available on the Fund’s website at www.aamlive.com.

Calendar Year Total Return

During the period of time shown in the bar chart, the Fund’s highest quarterly return was 0.81% for the quarter ended March 31, 2018 and the lowest quarterly return was -9.27% for the quarter ended June 30, 2018.

Average Annual Total Returns For the Periods Ended December 31, 2018

Average Annual Returns - AAM S&P Emerging Markets High Dividend Value ETF	Label	Average Annual Returns, 1 Year	Average Annual Returns, Since Inception	Average Annual Returns, Inception Date
AAM S&P Emerging Markets High Dividend Value ETF	Return Before Taxes	(14.42%)	(9.61%)	Nov. 28, 2017
After Taxes on Distributions | AAM S&P Emerging Markets High Dividend Value ETF	Return After Taxes on Distributions	(15.13%)	(10.33%)
After Taxes on Distributions and Sale of Fund Shares | AAM S&P Emerging Markets High Dividend Value ETF	Return After Taxes on Distributions and Sale of Fund Shares	(7.60%)	(6.96%)
S&P Emerging Markets Dividend and Free Cash Flow Yield Index (reflects no deduction for fees, expenses, or taxes)	S&P Emerging Markets Dividend and Free Cash Flow Yield Index (reflects no deduction for fees, expenses, or taxes)	(13.26%)	(8.58%)	Nov. 28, 2017
S&P Emerging Plus LargeMidCap® Index (reflects no deduction for fees, expenses, or taxes)	S&P Emerging Plus LargeMidCap® Index (reflects no deduction for fees, expenses, or taxes)	(13.85%)	(11.76%)	Nov. 28, 2017

After-tax returns are calculated using the historical highest individual federal marginal income tax rates during the period covered by the table above 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. In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures for the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.  After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as an individual retirement account (“IRA”) or other tax-advantaged accounts.

[1] Acquired Fund Fees and Expenses are the indirect costs of investing in other investment companies. Total Annual Fund Operating Expenses do not reflect Fund expenses paid indirectly and do not correlate to the expense ratios in the Fund's Financial Highlights because the Financial Highlights include only the direct operating expenses incurred by the Fund and exclude Acquired Fund Fees and Expenses.

XML

Label

Element

Value

AAM S&P Emerging Markets High Dividend Value ETF

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

AAM S&P Emerging Markets High Dividend Value ETF

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The AAM S&P Emerging Markets High Dividend Value ETF (the “Fund”) seeks to track the total return performance, before fees and expenses, of the S&P Emerging Markets Dividend and Free Cash Flow Yield Index (the “Index”).

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses of the Fund

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 (“Shares”). This table and the Example below do not include the brokerage commissions that investors may pay on their purchases and sales of 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)

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 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. For the fiscal period November 28, 2017 (commencement of operations) through October 31, 2018, the Fund’s portfolio turnover rate was 104% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

104.00%

Expense Exchange Traded Fund Commissions [Text]

rr_ExpenseExchangeTradedFundCommissions

This table and the Example below do not include the brokerage commissions that investors may pay on their purchases and sales of Shares.

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

Total Annual Fund Operating Expenses do not reflect Fund expenses paid indirectly and do not correlate to the expense ratios in the Fund’s Financial Highlights because the Financial Highlights include only the direct operating expenses incurred by the Fund and exclude Acquired Fund Fees and Expenses.

Expense Example [Heading]

rr_ExpenseExampleHeading

Expense 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 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 Fund uses a “passive management” (or indexing) approach to track the total return performance, before fees and expenses, of the Index.

S&P Emerging Markets Dividend and Free Cash Flow Yield Index

The Index is a rules-based, equal-weighted index that is designed to provide exposure to the constituents of the S&P Emerging Plus LargeMidCap Index that exhibit both high dividend yield and sustainable dividend distribution characteristics, while maintaining diversified sector exposure. The Index was developed in 2017 by S&P Dow Jones Indices, a division of S&P Global. The S&P Emerging Plus LargeMidCap Index is designed to measure the performance of large- and mid-capitalization securities in emerging markets. The S&P Emerging Plus LargeMidCap Index includes equity securities that are listed in Brazil, Chile, China, Colombia, the Czech Republic, Egypt, Greece, Hungary, India, Indonesia, Malaysia, Mexico, Pakistan, Peru, the Philippines, Poland, Qatar, Russia, South Africa, South Korea, Taiwan, Thailand, Turkey, and the United Arab Emirates (collectively, the “Emerging Markets”).

Construction of the Index begins with the universe of equity securities that are included in the S&P Emerging Plus LargeMidCap Index, have a minimum float-adjusted market capitalization of US$300 million, and have a median daily traded value of at least US$1 million. For each equity security in the S&P Emerging Plus LargeMidCap Index, the security’s dividend yield and free-cash-flow yield (i.e., a company’s cash flow from operations less capital expenditures divided by its market capitalization) are then adjusted to account for outliers. If a security’s dividend yield or free-cash-flow yield is in the top or bottom 2.5% of the S&P Emerging Plus LargeMidCap Index, the dividend yield or free-cash-flow yield, as applicable, for such security is replaced with the dividend yield or free-cash-flow yield of the security nearest to such top or bottom 2.5% threshold. The universe is then screened to keep only equity securities with a positive realized dividend yield (i.e., yield based on the total dividends paid for the most recent 12-month period) and free-cash-flow yield. The remaining securities are referred to as the “Selection Pool”.

For each security in the Selection Pool, the security’s dividend yield or free-cash-flow yield are then scored using a statistical normalization model (i.e., a tool to compare how close each yield is to the average yield for the Selection Pool) to assign a dividend yield score and free-cash-flow yield score from zero to one for each company. The equity securities in the Selection Pool are then ranked by the product of their dividend yield score and free-cash-flow yield score, and the top five scoring securities are selected from each sector (collectively, the “Index Constituents”). The Index uses Standard & Poor’s Global Industry Classification Standards to define companies within one of the following sectors: consumer discretionary, consumer staples, energy, financials, health care, industrials, information technology, materials, real estate, communication services, and utilities. Fewer than five securities may be selected if there are fewer than five securities in the Selection Pool for a given sector.

The Index is reconstituted (i.e., Index Constituents are added or deleted and weights are reset to equal-weight) semi-annually after the close of the last business day in January and July. At the time of each reconstitution of the Index, Index Constituents are added or deleted based on company data as of the last business day of December and June, respectively, and the Index Constituents are equally-weighted based on closing prices as of five business days prior to the last business day of the reconstitution month. If an Index Constituent is removed from the S&P Emerging Plus LargeMidCap Index, such security will simultaneously be removed from the Index. Additions to the Index Constituents only take place during the semi-annual reconstitutions. If multiple share classes of a single company qualify for inclusion in the Index, only the share class with the highest liquidity, measured by median daily value traded, is selected. As of December 31, 2018, the Index included significant exposure to companies in China, Taiwan, Brazil, and Russia.

The Fund’s Investment Strategy

The Fund attempts to invest all, or substantially all, of its assets in the component securities that make up the Index. Under normal circumstances, at least 80% of the Fund’s total assets (exclusive of any collateral held from securities lending) will be invested in the component securities of the Index and depositary receipts representing Index components. The Fund’s investment adviser expects that, over time, the correlation between the Fund’s performance and that of the Index, before fees and expenses, will be 95% or better.

The Fund will generally use a “replication” strategy to achieve its investment objective, meaning the Fund generally will invest in all of the component securities of the Index in approximately the same proportion as in the Index. However, the Fund may use a “representative sampling” strategy, meaning it may invest in a sample of the securities in the Index whose risk, return, and other characteristics closely resemble the risk, return, and other characteristics of the Index as a whole, when the Fund’s sub-adviser believes it is in the best interests of the Fund (e.g., when replicating the Index involves practical difficulties or substantial costs, an Index constituent becomes temporarily illiquid, unavailable, or less liquid, or as a result of legal restrictions or limitations that apply to the Fund but not to the Index).

The Fund generally may invest up to 20% of its total assets (exclusive of any collateral held from securities lending) in securities or other investments not included in the Index, but which the Fund’s sub-adviser believes will help the Fund track the Index. For example, the Fund may invest in securities that are not components of the Index to reflect various corporate actions and other changes to the Index (such as reconstitutions, additions, and deletions).

To the extent the Index concentrates (i.e., holds more than 25% of its total assets) in the securities of a particular industry or group of related industries, the Fund will concentrate its investments to approximately the same extent as the Index.

Risk [Heading]

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Principal Investment Risks

Risk Narrative [Text Block]

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The principal risks of investing in the Fund are summarized below. As with any investment, there is a risk that you could lose all or a portion of your investment in the Fund. The following riskscould affect the value of your investmentin the Fund:

· Capital Controls and Sanctions Risk. Economic conditions, such as volatile currency exchange rates and interest rates, political events, military action and other conditions may, without prior warning, lead to foreign government intervention (including intervention by the U.S. government with respect to foreign governments, economic sectors, foreign companies and related securities and interests) and the imposition of capital controls and/or sanctions, which may also include retaliatory actions of one government against another government, such as seizure of assets. Capital controls and/or sanctions include the prohibition of, or restrictions on, the ability to transfer currency, securities or other assets. Capital controls and/or sanctions may also impact the ability of the Fund to buy, sell or otherwise transfer securities or currency, negatively impact the value and/or liquidity of such instruments, adversely affect the trading market and price for shares of the Fund, and cause the Fund to decline in value.

· Currency Exchange Rate Risk. The Fund invests primarily in investments denominated in non-U.S. currencies or in securities that provide exposure to such currencies. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund’s investment and the value of your Shares. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money.

· Depositary Receipt Risk. Depositary Receipts involve risks similar to those associated with investments in foreign securities, such as changes in political or economic conditions of other countries and changes in the exchange rates of foreign currencies. Depositary Receipts listed on U.S. exchanges are issued by banks or trust companies, and entitle the holder to all dividends and capital gains that are paid out on the underlying foreign shares (“Underlying Shares”). When the Fund invests in Depositary Receipts as a substitute for an investment directly in the Underlying Shares, the Fund is exposed to the risk that the Depositary Receipts may not provide a return that corresponds precisely with that of the Underlying Shares.

· Equity Market Risk. The equity securities held in the Fund’s portfolio may experience sudden, unpredictable drops in value or long periods of decline in value. This may occur because of factors that affect securities markets generally or factors affecting specific issuers, industries, sectors or companies in which the Fund invests. Common stocks are generally exposed to greater risk than other types of securities, such as preferred stocks and debt obligations, because common stockholders generally have inferior rights to receive payment from issuers.

· Emerging Markets Risk. The Fund invests primarily in companies organized in emerging market nations. Investments in securities and instruments traded in developing or emerging markets, or that provide exposure to such securities or markets, can involve additional risks relating to political, economic, or regulatory conditions not associated with investments in U.S. securities and instruments or investments in more developed international markets. Such conditions may impact the ability of the Fund to buy, sell or otherwise transfer securities, adversely affect the trading market and price for Shares and cause the Fund to decline in value. Less information may be available about companies in emerging markets than in developed markets because such emerging markets companies may not subject to accounting, auditing and financial reporting standards or to other regulatory practices required by U.S. companies. 

· Foreign Securities Risk. Investments in non-U.S. securities involve certain risks that may not be present with investments in U.S. securities. For example, investments in non-U.S. securities may be subject to risk of loss due to foreign currency fluctuations or to political or economic instability. Investments in non-U.S. securities also may be subject to withholding or other taxes and may be subject to additional trading, settlement, custodial, and operational risks. These and other factors can make investments in the Fund more volatile and potentially less liquid than other types of investments.

· Geographic Investment Risk. To the extent the Fund invests a significant portion of its assets in the securities of companies of a single country or region, it is more likely to be impacted by events or conditions affecting that country or region.

o Risks of Investing in Brazil —Investments in securities of Brazilian companies are subject to regulatory and economic interventions that the Brazilian government has frequently exercised in the past, including the setting of wage and price controls, blocking access to bank accounts, imposing exchange controls and limiting imports. Investments are also subject to certain restrictions on foreign investment as provided by Brazilian law. The Brazilian economy has historically been subject to high rates of inflation and a high level of debt, all of which may stifle economic growth. Despite rapid development in recent years, Brazil still suffers from high levels of corruption, crime and income disparity. There is the possibility that such conditions may lead to social unrest and political upheaval in the future, which may have adverse effects on the Fund's investments.

o Risks of Investing in China — China may be subject to considerable degrees of economic, political and social instability. China is a developing market and demonstrates significantly higher volatility from time to time in comparison to developed markets. Over the past 25 years, the Chinese government has undertaken reform of economic and market practices and is expanding the sphere of private ownership of property in China. However, Chinese markets generally continue to experience inefficiency, volatility and pricing anomalies resulting from governmental influence, a lack of publicly available information and/or political and social instability. Internal social unrest or confrontations with other neighboring countries, including military conflicts in response to such events, may also disrupt economic development in China and result in a greater risk of currency fluctuations, currency convertibility, interest rate fluctuations and higher rates of inflation. Export growth continues to be a major driver of China’s rapid economic growth. Reduction in spending on Chinese products and services, institution of tariffs or other trade barriers, or a downturn in any of the economies of China’s key trading partners may have an adverse impact on the Chinese economy.

o Risks of Investing in Russia —Investment in securities of Russian issuers involves heightened risks not typically associated with investments in securities of issuers in more developed countries, including, among others, expropriation and/or nationalization of assets, restrictions on and government intervention in international trade, confiscatory or punitive taxation, regional conflict, political instability, including authoritarian and/or military involvement in governmental decision making, armed conflict, the imposition of economic sanctions by other nations, the impact on the economy as a result of civil unrest, and social instability as a result of religious, ethnic and/or socioeconomic unrest.

Securities markets in Russia are subject to greater risks associated with market volatility, lower market capitalization, lower trading volume, inflation, greater price fluctuations, uncertainty regarding the existence of trading markets, governmental control and heavy regulation of labor and industry.

The government in Russia may restrict or control to varying degrees the ability of foreign investors to invest in securities of issuers located or operating in Russia. These restrictions and/or controls may at times limit or prevent foreign investment in securities of issuers located or operating in Russia. Moreover, governmental approval or special licenses may be required prior to investments by foreign investors and may limit the amount of investments by foreign investors in a particular industry and/or issuer and may limit such foreign investment to a certain class of securities of an issuer that may have less advantageous rights than the classes available for purchase by domiciliaries of Russia and/or impose additional taxes on foreign investors.

Despite recent reform and privatization, the Russian government continues to control a large share of economic activity in the region. The Russian government owns shares in corporations in a range of sectors. Additionally, because Russia produces and exports large volumes of oil and gas, the Russian economy is particularly sensitive to the price of oil and gas on the world market, and a decline in the price of oil and gas could have a significant negative impact on the Russian economy. Current political and economic events in Russia and the effects of the recent global economic crisis on the Russian economy may have significant adverse effects on the Russian ruble and on the value and liquidity of the Fund’s investments.

o Risks of Investing in Taiwan — Taiwan is a small island state with few raw material resources and limited land area and is reliant on imports for its commodity needs. Any fluctuations or shortages in the commodity markets could have a negative impact on the Taiwanese economy. Also, continued labor outsourcing may adversely affect the Taiwanese economy. Taiwan’s economy is intricately linked with economies of Asian countries that have experienced over-extensions of credit, frequent and pronounced currency fluctuations, currency devaluations, currency repatriation, rising unemployment and fluctuations in inflation. The Taiwanese economy is dependent on the economies of Japan and China, as well as the United States, and negative changes in their economies or a reduction in purchases by any of them of Taiwanese products and services would likely have an adverse impact on the Taiwanese economy. Taiwan’s geographic proximity to China and Taiwan’s history of political contention with China have resulted in ongoing tensions with China, including the risk of war with China. These tensions may materially affect the Taiwanese economy and securities markets.

· Geopolitical Risk. Some countries and regions in which the Fund invests have experienced security concerns, war or threats of war and aggression, terrorism, economic uncertainty, natural and environmental disasters and/or systemic market dislocations that have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on the U.S. and world economies and markets generally, each of which may negatively impact the Fund’s investments.

· High Dividend Investing Risk. Companies with a high yield or payout ratio may reduce their dividend or stop paying dividends entirely while they are included in the Index. Such events could lower the price or yield of such company’s equity securities. Additionally, equity securities with a high yield or payout ratio may underperform other securities in certain market conditions.

· Limited Operating History Risk. The Fund is a recently organized, diversified management investment company with a limited operating history. As a result, prospective investors have a limited track record or history on which to base their investment decision.

· Market Risk. The trading prices of equity securities and other instruments fluctuate in response to a variety of factors. The Fund’s net asset value (“NAV”) and market price may fluctuate significantly in response to these and other factors. As a result, an investor could lose money over short or long periods of time.

· Passive Investment Risk. The Fund is not actively managed and its sub-adviser would not sell shares of an equity security due to current or projected underperformance of a security, industry or sector, unless that security is removed from the Index or the selling of shares of that security is otherwise required upon a rebalancing of the Index as addressed in the Index methodology.

· Portfolio Turnover Risk. The Fund may trade all or a significant portion of the securities in its portfolio in connection with each rebalance and reconstitution of its Index. A high portfolio turnover rate increases transaction costs, which may increase the Fund’s expenses. Frequent trading may also cause adverse tax consequences for investors in the Fund due to an increase in short-term capital gains.

· Shares May Trade at Prices Other Than NAV. As with all ETFs, Shares may be bought and sold in the secondary market at market prices. Although it is expected that the market price of Shares will approximate the Fund’s NAV, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount) due to supply and demand of Shares or during periods of market volatility. This risk is heightened in times of market volatility, periods of steep market declines, and periods when there is limited trading activity for Shares in the secondary market, in which case such premiums or discounts may be significant. Because securities held by the Fund trade on foreign exchanges that are closed when the Fund’s primary listing exchange is open, the Fund is likely to experience premiums and discounts greater than those of domestic ETFs.

· Smaller Companies Risk. The equity securities of smaller companies have historically been subject to greater investment risk than securities of larger companies. The prices of equity securities of smaller companies tend to be more volatile and less liquid than the prices of equity securities of larger companies.

· Tracking Error Risk. As with all index funds, the performance of the Fund and its Index may differ from each other for a variety of reasons. For example, the Fund incurs operating expenses and portfolio transaction costs not incurred by the Index. In addition, the Fund may not be fully invested in the securities of the Index at all times or may hold securities not included in the Index.

Risk Lose Money [Text]

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As with any investment, there is a risk that you could lose all or a portion of your investment in the Fund.

Bar Chart and Performance Table [Heading]

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Performance

Performance Narrative [Text Block]

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The following performance information indicates some of the risks of investing in the Fund. The bar chart shows the Fund’s performance for the calendar year ended December 31, 2018. The table illustrates how the Fund’s average annual returns for the 1‑year and since inception periods compare with those of a broad measure of market performance and the Index. The Fund’s past performance, before and after taxes, does not necessarily indicate how it will perform in the future. Updated performance information is also available on the Fund’s website at www.aamlive.com.

Performance Information Illustrates Variability of Returns [Text]

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The following performance information indicates some of the risks of investing in the Fund.

Performance Availability Website Address [Text]

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www.aamlive.com

Performance Past Does Not Indicate Future [Text]

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The Fund’s past performance, before and after taxes, does not necessarily indicate how it will perform in the future.

Bar Chart [Heading]

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Calendar Year Total Return

Bar Chart Closing [Text Block]

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During the period of time shown in the bar chart, the Fund’s highest quarterly return was 0.81% for the quarter ended March 31, 2018 and the lowest quarterly return was -9.27% for the quarter ended June 30, 2018.

Highest Quarterly Return, Label

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highest quarterly return

Highest Quarterly Return, Date

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Mar. 31, 2018

Highest Quarterly Return

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0.81%

Lowest Quarterly Return, Label

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lowest quarterly return

Lowest Quarterly Return, Date

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Jun. 30, 2018

Lowest Quarterly Return

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(9.27%)

Index No Deduction for Fees, Expenses, Taxes [Text]

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(reflects no deduction for fees, expenses, or taxes)

Performance Table Uses Highest Federal Rate

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After-tax returns are calculated using the historical highest individual federal marginal income tax rates during the period covered by the table above and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

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After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as an individual retirement account (“IRA”) or other tax-advantaged accounts.

Performance Table Explanation after Tax Higher

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In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures for the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.

Performance Table Closing [Text Block]

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After-tax returns are calculated using the historical highest individual federal marginal income tax rates during the period covered by the table above 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. In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures for the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.  After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as an individual retirement account (“IRA”) or other tax-advantaged accounts.

Caption

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Average Annual Total Returns For the Periods Ended December 31, 2018

AAM S&P Emerging Markets High Dividend Value ETF | S&P Emerging Markets Dividend and Free Cash Flow Yield Index (reflects no deduction for fees, expenses, or taxes)

Risk/Return:

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Label

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S&P Emerging Markets Dividend and Free Cash Flow Yield Index (reflects no deduction for fees, expenses, or taxes)

Average Annual Returns, 1 Year

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(13.26%)

Average Annual Returns, Since Inception

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(8.58%)

Average Annual Returns, Inception Date

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Nov. 28, 2017

AAM S&P Emerging Markets High Dividend Value ETF | S&P Emerging Plus LargeMidCap® Index (reflects no deduction for fees, expenses, or taxes)

Risk/Return:

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Label

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S&P Emerging Plus LargeMidCap® Index (reflects no deduction for fees, expenses, or taxes)

Average Annual Returns, 1 Year

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(13.85%)

Average Annual Returns, Since Inception

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(11.76%)

Average Annual Returns, Inception Date

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Nov. 28, 2017

AAM S&P Emerging Markets High Dividend Value ETF | AAM S&P Emerging Markets High Dividend Value ETF

Risk/Return:

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Management Fees

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0.49%

Distribution and Service (Rule 12b-1) Fees

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none

Other Expenses

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none

Acquired Fund Fees and Expenses

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0.01%

^[1]

Total Annual Fund Operating Expenses

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0.50%

Expense Example, with Redemption, 1 Year

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$ 51

Expense Example, with Redemption, 3 Years

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160

Expense Example, with Redemption, 5 Years

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280

Expense Example, with Redemption, 10 Years

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$ 628

Annual Return 2018

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(14.42%)

Label

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Return Before Taxes

Average Annual Returns, 1 Year

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(14.42%)

Average Annual Returns, Since Inception

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(9.61%)

Average Annual Returns, Inception Date

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Nov. 28, 2017

AAM S&P Emerging Markets High Dividend Value ETF | AAM S&P Emerging Markets High Dividend Value ETF | After Taxes on Distributions

Risk/Return:

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Label

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Return After Taxes on Distributions

Average Annual Returns, 1 Year

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(15.13%)

Average Annual Returns, Since Inception

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(10.33%)

AAM S&P Emerging Markets High Dividend Value ETF | AAM S&P Emerging Markets High Dividend Value ETF | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

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Label

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Return After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

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(7.60%)

Average Annual Returns, Since Inception

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(6.96%)

[1] Acquired Fund Fees and Expenses are the indirect costs of investing in other investment companies. Total Annual Fund Operating Expenses do not reflect Fund expenses paid indirectly and do not correlate to the expense ratios in the Fund's Financial Highlights because the Financial Highlights include only the direct operating expenses incurred by the Fund and exclude Acquired Fund Fees and Expenses.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Prospectus Date	rr_ProspectusDate	Feb. 28, 2019