S000003468 [Member] Fees and Expenses - Sit Minnesota Tax-Free Income Fund	Mar. 31, 2025
Prospectus [Line Items]
Expense Heading [Optional Text]	FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]	This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables or the examples below.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]	The total annual fund operating expenses do not correlate to the ratio of expenses to average net assets shown in the Fund’s Financial Highlights, which does not include Acquired Fund Fees and Expenses. Acquired Fund Fees and Expenses represent fees and expenses incurred indirectly by the Fund as a result of its investment in shares of investment companies.
Shareholder Fees Caption [Optional Text]	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Optional Text]	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading]	Example
Expense Example Narrative [Text Block]	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in the Fund for the time periods indicated, that your investment has a 5% return each year, that the Fund’s operating expenses remain the same, and that you redeem all of your shares at the end of those periods. Although your actual costs and returns may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover [Heading]	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	The Fund pays transactions 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 in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 10.29% of the average value of the portfolio.
Portfolio Turnover, Rate	10.29%

S000003468 [Member] Fees and Expenses - Sit Minnesota Tax-Free Income Fund

Mar. 31, 2025

FEES AND EXPENSES OF THE FUND

This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables or the examples below.

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

The total annual fund operating expenses do not correlate to the ratio of expenses to average net assets shown in the Fund’s Financial Highlights, which does not include Acquired Fund Fees and Expenses. Acquired Fund Fees and Expenses represent fees and expenses incurred indirectly by the Fund as a result of its investment in shares of investment companies.

Shareholder Fees Caption [Optional Text]

Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Optional Text]

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

Expense Example [Heading]

Example

Expense Example Narrative [Text Block]

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in the Fund for the time periods indicated, that your investment has a 5% return each year, that the Fund’s operating expenses remain the same, and that you redeem all of your shares at the end of those periods. Although your actual costs and returns may be higher or lower, based on these assumptions your costs would be:

Portfolio Turnover [Heading]

PORTFOLIO TURNOVER

Portfolio Turnover [Text Block]

The Fund pays transactions 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 in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 10.29% of the average value of the portfolio.

Portfolio Turnover, Rate

10.29%