Label	Element	Value
Class F Prospectus \| SIT INTERNATIONAL FIXED INCOME FUND
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	SIT INTERNATIONAL FIXED INCOME FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Capital appreciation and current income.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold Fund shares.
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 58% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	58.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal circumstances, the International Fixed Income Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in fixed income securities. The Fund will invest primarily in investment grade foreign government and corporate fixed income securities, as well as foreign mortgage-backed and/or asset-backed fixed income securities, of issuers located in at least three countries other than the U.S. (including, to a lesser extent, emerging market countries). It is expected that at least 40% of the Fund's assets will be invested in non-U.S. securities. Other fixed income securities in which the Fund may invest include: (i) securities issued or guaranteed by the U.S. Government and its agencies and instrumentalities and obligations of U.S. commercial banks, such as certificates of deposit, time deposits, bankers' acceptances and bank notes; (ii) U.S. corporate debt securities and mortgage-backed and asset-backed securities; and (iii) obligations of supranational entities. The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser. In selecting investments for the Fund, the Sub-Advisers choose securities issued by corporations and governments located in various countries, looking for opportunities to achieve capital appreciation and gain, as well as current income. There are no restrictions on the Fund's average portfolio maturity or on the maturity of any specific security. The Sub-Advisers may seek to enhance the Fund's return by actively managing the Fund's foreign currency exposure. In managing the Fund's currency exposure, the Sub-Advisers buy and sell currencies (i.e., take long or short positions) using derivatives, principally futures, foreign currency forward contracts and currency swaps. The Fund may take long and short positions in foreign currencies in excess of the value of the Fund's assets denominated in a particular currency or when the Fund does not own assets denominated in that currency. The Fund may also engage in currency transactions in an attempt to take advantage of certain inefficiencies in the currency exchange market, to increase its exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. In managing the Fund's currency exposure from foreign securities, the Sub-Advisers may buy and sell currencies for hedging or for speculative purposes. The Fund may also invest in futures contracts, forward contracts and swaps for speculative or hedging purposes. Futures contracts, forward contracts and swaps are used to synthetically obtain exposure to the securities identified above or baskets of such securities and to manage the Fund's interest rate duration and yield curve exposure. These derivatives are also used to mitigate the Fund's overall level of risk and/or the Fund's risk to particular types of securities, currencies or market segments. Interest rate swaps are further used to manage the Fund's yield spread sensitivity. When the Fund seeks to take an active long or short position with respect to the likelihood of an event of default of a security or basket of securities, the Fund may use credit default swaps. The Fund may buy credit default swaps in an attempt to manage credit risk where the Fund has credit exposure to an issuer and the Fund may sell credit default swaps to more efficiently gain credit exposure to such security or basket of securities. The Fund will also invest in securities rated below investment grade (junk bonds). However, in general, the Fund will purchase bonds with a rating of CCC or above. The Fund also invests a portion of its assets in bank loans, which are generally non-investment grade floating rate instruments. The Fund may invest in bank loans in the form of participations in the loans or assignments of all or a portion of the loans from third parties. The Fund may purchase shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Market Risk — The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. Generally, the Fund's fixed income securities will decrease in value if interest rates rise and vice versa. In a low interest rate environment, risks associated with rising rates are heightened. Declines in dealer market-making capacity as a result of structural or regulatory changes could further decrease liquidity and/or increase volatility in the fixed income markets. In the case of foreign securities, price fluctuations will reflect international economic and political events, as well as changes in currency valuations relative to the U.S. dollar. In response to these events, the Fund's value may fluctuate and/or the Fund may experience increased redemptions from shareholders, which may impact the Fund's liquidity or force the Fund to sell securities into a declining or illiquid market. Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries. Investment Style Risk — The risk that developed international fixed income securities may underperform other segments of the fixed income markets or the fixed income markets as a whole. Non-Diversified Risk — The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities. However, the Fund intends to satisfy the asset diversification requirements under the Internal Revenue Code of 1986, as amended (the Code) for classification as a regulated investment company (RIC). Interest Rate Risk — The risk that a rise in interest rates will cause a fall in the value of fixed income securities, including U.S. Government securities, in which the Fund invests. A low interest rate environment may present greater interest rate risk, because there may be a greater likelihood of rates increasing and rates may increase more rapidly. Duration Risk — The longer-term securities in which the Fund may invest tend to be more volatile than shorter-term securities. A portfolio with a longer average portfolio duration is more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. Corporate Fixed Income Securities Risk — Corporate fixed income securities respond to economic developments, especially changes in interest rates, as well as perceptions of the creditworthiness and business prospects of individual issuers. Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation. Foreign Sovereign Debt Securities Risk — The risks that: (i) the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or interest when it becomes due because of factors such as debt service burden, political constraints, cash flow problems and other national economic factors; (ii) governments may default on their debt securities, which may require holders of such securities to participate in debt rescheduling or additional lending to defaulting governments; and (iii) there is no bankruptcy proceeding by which defaulted sovereign debt may be collected in whole or in part. Derivatives Risk — The Fund's use of swaps, futures and forward contracts is subject to market risk, leverage risk, correlation risk and liquidity risk. Market risk is described above, and leverage risk and liquidity risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of swaps and forward contracts is also subject to credit risk and valuation risk. Credit risk is described above. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear. Currency Risk — As a result of the Fund's investments in securities or other investments denominated in, and/or receiving revenues in, foreign currencies and the Fund's active management of its currency exposures, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Due to the Fund's active positions in currencies, it will be subject to the risk that currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad. Asset-Backed Securities Risk — Payment of principal and interest on asset-backed securities is dependent largely on the cash flows generated by the assets backing the securities. Securitization trusts generally do not have any assets or sources of funds other than the receivables and related property they own, and asset-backed securities are generally not insured or guaranteed by the related sponsor or any other entity. Asset-backed securities may be more illiquid than more conventional types of fixed-income securities that the Fund acquires. Below Investment Grade Securities (Junk Bonds) Risk — Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are generally more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Because these securities typically offer a higher rate of return to compensate investors for these risks, they are sometimes referred to as "high yield bonds," but there is no guarantee that an investment in these securities will result in a high rate of return. Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss. Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance. U.S. Government Securities Risk — Although U.S. Government securities are considered to be among the safest investments, they are not guaranteed against price movements due to changing interest rates. Obligations issued by some U.S. Government agencies are backed by the U.S. Treasury, while others are backed solely by the ability of the agency to borrow from the U.S. Treasury or by the agency's own resources. Bank Loans Risk — With respect to bank loans, the Fund will assume the credit risk of both the borrower and the lender that is selling the participation. The Fund may also have difficulty disposing of bank loans because, in certain cases, the market for such instruments is not highly liquid. Mortgage-Backed Securities Risk — Mortgage-backed securities are affected significantly by the rate of prepayments and modifications of the mortgage loans backing those securities, as well as by other factors such as borrower defaults, delinquencies, realized or liquidation losses and other shortfalls. Mortgage-backed securities are particularly sensitive to prepayment risk, which is described below, given that the term to maturity for mortgage loans is generally substantially longer than the expected lives of those securities; however, the timing and amount of prepayments cannot be accurately predicted. The timing of changes in the rate of prepayments of the mortgage loans may significantly affect the Fund's actual yield to maturity on any mortgage-backed securities, even if the average rate of principal payments is consistent with the Fund's expectation. Along with prepayment risk, mortgage-backed securities are significantly affected by interest rate risk, which is described above. In a low interest rate environment, mortgage loan prepayments would generally be expected to increase due to factors such as refinancing and loan modifications at lower interest rates. In contrast, if prevailing interest rates rise, prepayments of mortgage loans would generally be expected to decline and therefore extend the weighted average lives of mortgage-backed securities held or acquired by the Fund. Extension Risk — The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value. Prepayment Risk — The risk that in a declining interest rate environment, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates. LIBOR Replacement Risk — The elimination of the London Inter-Bank Offered Rate (LIBOR) may adversely affect the interest rates on, and value of, certain Fund investments for which the value is tied to LIBOR. It remains unclear if LIBOR will continue to exist in its current form or will be modified after 2021, or whether the market will adopt one or more alternative rates. It will be difficult to predict the full impact of the transition away from LIBOR on the Fund until new reference rates and market practices have been commercially accepted. Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses. Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Risk Lose Money [Text]	rr_RiskLoseMoney	You could lose money on your investment in the Fund, just as you could with other investments.
Risk Nondiversified Status [Text]	rr_RiskNondiversifiedStatus	The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities. However, the Fund intends to satisfy the asset diversification requirements under the Internal Revenue Code of 1986, as amended (the Code) for classification as a regulated investment company (RIC).
RIsk Not Insured [Text]	rr_RiskNotInsured	An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-800-DIAL-SEI
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 3.51% (09/30/10) Worst Quarter: -3.02% (06/30/15)
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2010
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	3.51%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Jun. 30, 2015
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(3.02%)
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	(reflects no deduction for fees, expenses or taxes)
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Average Annual Return, Caption	rr_AverageAnnualReturnCaption	Average Annual Total Returns (for the periods ended December 31, 2019)
Class F Prospectus \| SIT INTERNATIONAL FIXED INCOME FUND \| Bloomberg Barclays Global Aggregate ex-US Index, Hedged Return (reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Bloomberg Barclays Global Aggregate ex-US Index, Hedged Return (reflects no deduction for fees, expenses or taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	7.57%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	3.87%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	4.29%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	5.62%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 01, 1993
Class F Prospectus \| SIT INTERNATIONAL FIXED INCOME FUND \| SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A)
Risk/Return:	rr_RiskReturnAbstract
Management Fees	rr_ManagementFeesOverAssets	0.30%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.77%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.07%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 109
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	340
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	590
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,306
Annual Return 2010	rr_AnnualReturn2010	5.33%
Annual Return 2011	rr_AnnualReturn2011	3.51%
Annual Return 2012	rr_AnnualReturn2012	6.68%
Annual Return 2013	rr_AnnualReturn2013	(0.11%)
Annual Return 2014	rr_AnnualReturn2014	7.92%
Annual Return 2015	rr_AnnualReturn2015	0.39%
Annual Return 2016	rr_AnnualReturn2016	4.56%
Annual Return 2017	rr_AnnualReturn2017	1.79%
Annual Return 2018	rr_AnnualReturn2018	1.93%
Annual Return 2019	rr_AnnualReturn2019	6.55%
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	6.55%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	3.02%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	3.82%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	4.27%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 01, 1993
Class F Prospectus \| SIT INTERNATIONAL FIXED INCOME FUND \| SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A) \| After Taxes on Distributions
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return After Taxes on Distributions
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.30%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	1.73%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	2.38%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	2.72%
Class F Prospectus \| SIT INTERNATIONAL FIXED INCOME FUND \| SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A) \| 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	4.15%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	1.77%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	2.36%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	2.72%

If the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph ii