| Form N-CSR Cover | 12 Months Ended |
| Jun. 30, 2024 | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSR |
| Amendment Flag | false |
| Registrant Name | DUPREE MUTUAL FUNDS |
| Entity Central Index Key | 0000311101 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | Jun. 30, 2024 |
| Shareholder Report | 12 Months Ended |
| Jun. 30, 2024 USD ($) Holding | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSR |
| Amendment Flag | false |
| Registrant Name | DUPREE MUTUAL FUNDS |
| Entity Central Index Key | 0000311101 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | Jun. 30, 2024 |
| Alabama Tax-Free Income Series | |
| Shareholder Report [Line Items] | |
| Fund Name | Alabama Tax-Free Income Series |
| Class Name | Alabama Tax-Free Income Series |
| Trading Symbol | DUALX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Alabama Tax-Free |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the Fund at www.dupree-funds.com/documents. 866-0614 |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | (800) 866-0614 |
| Additional Information Email | info@dupree-funds.com |
| Additional Information Website | www.dupree-funds.com/documents |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) The below table explains the costs that you would have paid within the reporting period. Fund (Class) Costs of a $10,000 investment Costs paid as a percentage of a Alabama Tax-Free $ 70 0.70% |
| Expenses Paid, Amount | $ 70 |
| Expense Ratio, Percent | 0.70% |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year? During the reporting period, longer-dated, lower-rated municipal bonds generally outperformed shorter-dated, higher-rated bonds. The Fund provided a total return of 3.17% during the reporting period which was roughly in line with the Bloomberg Municipal Bond Index (the “Muni Index”) which returned 3.21%. The Fund’s slight underperformance was primarily due to the fact that it held fewer “BBB” rated bonds and had a shorter duration than the Muni Index. Additionally, unlike the Fund, the Muni Index does not reflect any expenses and/or transaction costs. During the reporting period, the Fund’s use of its current investment strategies did not cause the Fund’s performance to deviate materially from the manager’s expectations. We do not plan to change the investment strategy of the Fund substantially in the upcoming year. |
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance is not a good predictor of the Fund’s future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total return values (as of June 30, 2024): 1 Year 5 Years 10 Years Alabama Tax-Free 3.17 % 0.82 % 2.03 % Bloomberg Municipal Bond Index 3.21 % 1.16 % 2.39 % |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder |
| Net Assets | $ 20,654,451 |
| Holdings Count | Holding | 70 |
| Advisory Fees Paid, Amount | $ 61,315 |
| Investment Company, Portfolio Turnover | 20.02% |
| Additional Fund Statistics [Text Block] | What are the Key Fund statistics you should know? The following table outlines key Fund statistics that you should pay attention to: Fund’s net assets $ 20,654,451 Total number of portfolio holdings 70 Net advisory fees paid $ 61,315 Portfolio turnover rate as of the end of the reporting period 20.02% |
| Holdings [Text Block] | What is the Fund invested in? The tables and charts below show the investment makeup of the Fund, representing the percentage of total net assets of the Fund. Composition Credit Quality* Ratings have been assigned by a Nationally Recognized Statistical Rating Organizations (“NRSRO”). All ratings are by Moody’s Ratings, an NRSRO, unless noted otherwise. Moody’s Ratings was selected because it is recognized as a leading NRSRO that offers a transparent and reliable rating process for debt instruments. See Schedules of Portfolio Investments for individual bond ratings. Visit our website at www.dupree-funds.com/documents. |
| Updated Prospectus Web Address | www.dupree-funds.com/documents |
| Kentucky Tax-Free Income Series | |
| Shareholder Report [Line Items] | |
| Fund Name | Kentucky Tax-Free Income Series |
| Class Name | Kentucky Tax-Free Income Series |
| Trading Symbol | KYTFX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Kentucky Tax-Free |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the Fund at www.dupree-funds.com/documents. 866-0614 |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | (800) 866-0614 |
| Additional Information Email | info@dupree-funds.com |
| Additional Information Website | www.dupree-funds.com/documents |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) The below table explains the costs that you would have paid within the reporting period. Fund (Class) Costs of a $10,000 investment Costs paid as a percentage of a Kentucky Tax-Free $ 62 0.62% |
| Expenses Paid, Amount | $ 62 |
| Expense Ratio, Percent | 0.62% |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year? During the reporting period, longer-dated, lower-rated municipal bonds generally outperformed shorter-dated, higher-rated bonds. The Fund provided a total return of 3.03% during the reporting period which was roughly in line with the Bloomberg Municipal Bond Index (“Muni Index”) which returned 3.21%. The Fund’s slight underperformance was primarily due to the fact that it held fewer “BBB” rated bonds and had a shorter duration than the Muni Index. Additionally, unlike the Fund, the Muni Index does not reflect any expenses and/or transaction costs. During the reporting period, the Fund’s use of its current investment strategies did not cause the Fund’s performance to deviate materially from the manager’s expectations. We do not plan to change the investment strategy of the Fund substantially in the upcoming year. |
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance is not a good predictor of the Fund’s future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total return values (as of June 30, 2024): 1 Year 5 Years 10 Years Kentucky Tax-Free Income Series 3.03 % 0.88 % 1.95 % Bloomberg Municipal Bond Index 3.21 % 1.16 % 2.39 % |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Net Assets | $ 736,956,373 |
| Holdings Count | Holding | 322 |
| Advisory Fees Paid, Amount | $ 3,032,606 |
| Investment Company, Portfolio Turnover | 14.50% |
| Additional Fund Statistics [Text Block] | What are the Key Fund statistics you should know? The following table outlines key Fund statistics that you should pay attention to: Fund’s net assets $ 736,956,373 Total number of portfolio holdings 322 Total advisory fees paid $ 3,032,606 Portfolio turnover rate as of the end of the reporting period 14.50% |
| Holdings [Text Block] | What is the Fund invested in? The tables and charts below show the investment makeup of the Fund, representing the percentage net Composition Credit Quality* Ratings have been assigned by a Nationally Recognized Statistical Rating Organizations (“NRSRO”). All ratings are by Moody’s Ratings, an NRSRO, unless noted otherwise. Moody’s Ratings was selected because it is recognized as a leading NRSRO that offers a transparent and reliable rating process for debt instruments. See Schedules of Portfolio Investments for individual bond ratings. Visit our website at www.dupree-funds.com/documents. |
| Updated Prospectus Web Address | www.dupree-funds.com/documents |
| Kentucky Tax-Free Short-to-Medium Series | |
| Shareholder Report [Line Items] | |
| Fund Name | Kentucky Tax-Free Short-to-Medium Series |
| Class Name | Kentucky Tax-Free Short-to-Medium Series |
| Trading Symbol | KYSMX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Kentucky Tax-Free Short-to-Medium |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the Fund at www.dupree-funds.com/documents. You can also request this information by contacting us at (800) 866-0614 |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | (800) 866-0614 |
| Additional Information Email | info@dupree-funds.com |
| Additional Information Website | www.dupree-funds.com/documents |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) The below table explains the costs that you would have paid within the reporting period. Fund (Class) Costs of a $10,000 investment Costs paid as a percentage of a Ke ntucky Tax-Free Short-to-Medum $ 70 0.70% |
| Expenses Paid, Amount | $ 70 |
| Expense Ratio, Percent | 0.70% |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year? During the reporting period, longer-dated, lower-rated municipal bonds generally outperformed shorter-dated, higher-rated bonds, The Fund provided a total return of 1.83% during the reporting period which was lower than the Bloomberg Municipal Bond Index (the “Muni Index”) which returned 3.21%. The Fund’s underperformance was due primarily to the fact that it held fewer “BBB” rated bonds and had a substantially shorter duration than the Muni Index. During the reporting period, the Fund’s use of its current investment strategy did not cause the Fund’s performance to deviate materially from the manager’s expectations. We do not plan to change the investment strategy of the Fund substantially in the upcoming year. |
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance is not a good predictor of the Fund’s future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total return values (as of June 30, 2024): 1 Year 5 Years 10 Years Kentucky Tax-Free Short-to-Medium 1.83 % 0.70 % 1.16 % Bloomberg Municipal Bond Index 3.21 % 1.16 % 2.39 % |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Net Assets | $ 31,676,562 |
| Holdings Count | Holding | 54 |
| Advisory Fees Paid, Amount | $ 134,414 |
| Investment Company, Portfolio Turnover | 24.89% |
| Additional Fund Statistics [Text Block] | What are the Key Fund statistics you should know? The following table outlines key Fund statistics that you should pay attention to: Fund’s net assets $ 31,676,562 Total number of portfolio holdings 54 Net advisory fees paid $ 134,414 Portfolio turnover rate as of the end of the reporting period 24.89% |
| Holdings [Text Block] | What is the Fund invested in? The tables and charts below show the investment makeup of the Fund, representing the percentage of total net assets of the Fund. Composition Credit Quality* Ratings have been assigned by a Nationally Recognized Statistical Rating Organizations (“NRSRO”). All ratings are by Moody’s Ratings, an NRSRO, unless noted otherwise. Moody’s Ratings was selected because it is recognized as a leading NRSRO that offers a transparent and reliable rating process for debt instruments. See Schedules of Portfolio Investments for individual bond ratings. Visit our website at www.dupree-funds.com/documents. |
| Updated Prospectus Web Address | www.dupree-funds.com/documents |
| Mississippi Tax-Free Income Series | |
| Shareholder Report [Line Items] | |
| Fund Name | Mississippi Tax-Free Income Series |
| Class Name | Mississippi Tax-Free Income Series |
| Trading Symbol | DUMSX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Mississippi Tax-Free |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the Fund at www.dupree-funds.com/documents. (800) 866-0614 |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | (800) 866-0614 |
| Additional Information Email | info@dupree-funds.com |
| Additional Information Website | www.dupree-funds.com/documents |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) The below table explains the costs that you would have paid within the reporting period. Fund (Class) Costs of a $10,000 investment Costs paid as a percentage of a Mississippi Tax-Free $ 70 0.70% |
| Expenses Paid, Amount | $ 70 |
| Expense Ratio, Percent | 0.70% |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year? During the reporting period, longer-dated, lower-rated municipal bonds generally outperformed shorter-dated, higher-quality bonds. The Fund provided a total return of 2.60% during the Review Period which was lower than the Bloomberg Municipal Bond Index (the “Muni Index”) which returned 3.21%. The underperformance of the Fund was due primarily to the fact that the Fund held fewer “BBB” rated bonds and had a shorter duration than the Muni Index. Additionally, unlike the Fund, the Muni Index does not reflect any expenses and/or transaction costs. During the reporting period, the Fund’s use of its current investment strategy did not cause the Fund’s performance to deviate materially from the manager’s expectations. We do not plan to change the investment strategy of the Fund substantially in the upcoming year. |
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance is not a good predictor of the Fund’s future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total return values (as of June 30, 2024): 1 Year 5 Years 10 Years Mississippi Tax-Free 2.60 % 0.51 % 1.93 % Bloomberg Municipal Bond Index 3.21 % 1.16 % 2.39 % |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Net Assets | $ 9,606,748 |
| Holdings Count | Holding | 54 |
| Advisory Fees Paid, Amount | $ 22,647 |
| Investment Company, Portfolio Turnover | 17.87% |
| Additional Fund Statistics [Text Block] | What are the Key Fund statistics you should know? The following table outlines key Fund statistics that you should pay attention to: Fund’s net assets $ 9,606,748 Total number of portfolio holdings 54 Net advisory fees paid $ 22,647 Portfolio turnover rate as of the end of the reporting period 17.87% |
| Holdings [Text Block] | What is the Fund invested in? The tables and charts below show the investment makeup of the Fund, representing the percentage of total net assets of the Fund. Composition Credit Quality* Ratings have been assigned by a Nationally Recognized Statistical Rating Organizations (“NRSRO”). All ratings are by Moody’s Ratings, an NRSRO, unless noted otherwise. Moody’s Ratings was selected because it is recognized as a leading NRSRO that offers a transparent and reliable rating process for debt instruments. See Schedules of Portfolio Investments for individual bond ratings. Visit our website at www.dupree-funds.com/documents. |
| Updated Prospectus Web Address | www.dupree-funds.com/documents |
| North Carolina Tax-Free Income Series | |
| Shareholder Report [Line Items] | |
| Fund Name | North Carolina Tax-Free Income Series |
| Class Name | North Carolina Tax-Free Income Series |
| Trading Symbol | NTFIX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the North Carolina Tax-Free |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the Fund at www.dupree-funds.com/documents. (800) 866-0614 |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | (800) 866-0614 |
| Additional Information Email | info@dupree-funds.com |
| Additional Information Website | www.dupree-funds.com/documents |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) The below table explains the costs that you would have paid within the reporting period. Fund (Class) Costs of a $10,000 investment Costs paid as a percentage of a North Carolina Tax-Free $ 70 0.70% |
| Expenses Paid, Amount | $ 70 |
| Expense Ratio, Percent | 0.70% |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year? During the reporting period, longer-dated, lower-rated municipal bonds generally outperformed shorter-dated, higher-rated bonds. The Fund provided a total return of 2.89% during the reporting period which was lower than the Bloomberg Municipal Bond Index (the “Muni Index”) which returned 3.21%. The underperformance of the Fund was due primarily to the fact that it held fewer “BBB” rated bonds and had a shorter duration than the Muni Index. Additionally, unlike the Fund, the Muni Index does not reflect any expenses and/or transaction costs. During the reporting period, the Fund’s use of its current investment strategy did not cause the Fund’s performance to deviate materially from the manager’s expectations. We do not plan to change the investment strategy of the Fund substantially in the upcoming year. |
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance is not a good predictor of the Fund’s future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total return values (as of June 30, 2024): 1 Year 5 Years 10 Years North Carolina Tax-Free 2.89 % 0.57 % 1.81 % Bloomberg Municipal Bond Index 3.21 % 1.16 % 2.39 % |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Net Assets | $ 115,374,466 |
| Holdings Count | Holding | 161 |
| Advisory Fees Paid, Amount | $ 513,458 |
| Investment Company, Portfolio Turnover | 11.99% |
| Additional Fund Statistics [Text Block] | What are the Key Fund statistics you should know? The following table outlines key Fund statistics that you should pay attention to: Fund’s net assets $ 115,374,466 Total number of portfolio holdings 161 Net advisory fees paid $ 513,458 Portfolio turnover rate as of the end of the reporting period 11.99% |
| Holdings [Text Block] | What is the Fund invested in? The tables and charts below show the investment makeup of the Fund, representing the percentage of total net assets of the Fund. Composition Credit Quality* Ratings have been assigned by a Nationally Recognized Statistical Rating Organizations (“NRSRO”). All ratings are by Moody’s Ratings, an NRSRO, unless noted otherwise. Moody’s Ratings was selected because it is recognized as a leading NRSRO that offers a transparent and reliable rating process for debt instruments. See Schedules of Portfolio Investments for individual bond ratings. Visit our website at www.dupree-funds.com/documents. |
| Updated Prospectus Web Address | www.dupree-funds.com/documents |
| North Carolina Tax-Free Short-to-Medium Series | |
| Shareholder Report [Line Items] | |
| Fund Name | North Carolina Tax-Free Short-to-Medium Series |
| Class Name | North Carolina Tax-Free Short-to-Medium Series |
| Trading Symbol | NTSMX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the North Carolina Tax-Free Short-to-Medium |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the Fund at www.dupree-funds.com/documents. You can also request this information by contacting us at (800) 866-0614 |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | (800) 866-0614 |
| Additional Information Email | info@dupree-funds.com |
| Additional Information Website | www.dupree-funds.com/documents |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) The below table explains the costs that you would have paid within the reporting period. Fund (Class) Costs of a $10,000 investment Costs paid as a percentage of a North Carolina Tax-Free Short-to-Medium $ 70 0.70% |
| Expenses Paid, Amount | $ 70 |
| Expense Ratio, Percent | 0.70% |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year? During the reporting period, longer-dated, lower-rated municipal bonds generally outperformed shorter-dated, higher-rated bonds. The Fund provided a total return of 1.71% during the reporting period which was lower than the Bloomberg Municipal Bond Index (the “Muni Index”) which returned 3.21%. The Fund’s underperformance was due primarily to the fact that it held fewer “BBB” rated bonds and had a substantially shorter duration than the Muni Index. During the reporting period, the Fund’s use of its current management strategy did not cause the performance to deviate materially from the manager’s expectations. We do not plan to change the investment strategy of the Fund substantially in the upcoming year. |
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance is not a good predictor of the Fund’s future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total return values (as of June 30, 2024): 1 Year 5 Years 10 Years North Carolina Tax-Free Short-to-Medium 1.71 % 0.37 % 0.93 % Bloomberg Municipal Bond Index 3.21 % 1.16 % 2.39 % |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Net Assets | $ 9,016,977 |
| Holdings Count | Holding | 38 |
| Advisory Fees Paid, Amount | $ 23,315 |
| Investment Company, Portfolio Turnover | 0% |
| Additional Fund Statistics [Text Block] | What are the Key Fund statistics you should know? The following table outlines key Fund statistics that you should pay attention to: Fund’s net assets $ 9,016,977 Total number of portfolio holdings 38 Net advisory fees paid $ 23,315 Portfolio turnover rate as of the end of the reporting period 0.00% |
| Holdings [Text Block] | What is the Fund invested in? The tables and charts below show the investment makeup of the Fund, representing the percentage of total net assets of the Fund. Composition Credit Quality* Ratings have been assigned by a Nationally Recognized Statistical Rating Organizations (“NRSRO”). All ratings are by Moody’s Ratings, an NRSRO, unless noted otherwise. Moody’s Ratings was selected because it is recognized as a leading NRSRO that offers a transparent and reliable rating process for debt instruments. See Schedules of Portfolio Investments for individual bond ratings. Visit our website at www.dupree-funds.com/documents. |
| Updated Prospectus Web Address | www.dupree-funds.com/documents |
| Tennessee Tax-Free Income Series | |
| Shareholder Report [Line Items] | |
| Fund Name | Tennessee Tax-Free Income Series |
| Class Name | Tennessee Tax-Free Income Series |
| Trading Symbol | TNTIX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Tennessee Tax-Free |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the Fund at www.dupree-funds.com/documents. 866-0614 |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | (800) 866-0614 |
| Additional Information Email | info@dupree-funds.com |
| Additional Information Website | www.dupree-funds.com/documents |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) The below table explains the costs that you would have paid within the reporting period. Fund (Class) Costs of a $10,000 investment Costs paid as a percentage of a Tennessee Tax-Free $ 70 0.70% |
| Expenses Paid, Amount | $ 70 |
| Expense Ratio, Percent | 0.70% |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year? During the reporting period, longer-dated, lower-rated municipal bonds generally outperformed shorter-dated, higher-quality bonds. The Fund provided a total return of 2.82% during the reporting period which was lower than the Bloomberg Municipal Bond Index (the “Muni Index”) which returned 3.21%. The underperformance of the Fund was primarily due to the fact that the Fund held fewer “BBB” rated bonds and had a shorter duration than the Muni Index. Additionally, unlike the Fund, the Muni Index does not reflect any expenses and/or transaction costs During the reporting period, the Fund’s use of its current investment strategy did not cause the Fund’s performance to deviate materially from the manager’s expectations. We do not plan to change the investment strategy of the Fund substantially in the upcoming year. |
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance is not a good predictor of the Fund’s future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total return values (as of June 30, 2024): 1 Year 5 Years 10 Years Tennessee Tax-Free 2.82 % 0.78 % 1.79 % Bloomberg Municipal Bond Index 3.21 % 1.16 % 2.39 % |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Net Assets | $ 53,592,111 |
| Holdings Count | Holding | 69 |
| Advisory Fees Paid, Amount | $ 227,110 |
| Investment Company, Portfolio Turnover | 21.15% |
| Additional Fund Statistics [Text Block] | What are the Key Fund statistics you should know? The following table outlines key Fund statistics that you should pay attention to: Fund’s net assets $ 53,592,111 Total number of portfolio holdings 69 Net advisory fees paid $ 227,110 Portfolio turnover rate as of the end of the reporting period 21.15% |
| Holdings [Text Block] | What is the Fund invested in? The tables and charts below show the investment makeup of the Fund, representing the percentage of total net assets of the Fund. Composition Credit Quality* Ratings have been assigned by a Nationally Recognized Statistical Rating Organizations (“NRSRO”). All ratings are by Moody’s Ratings, an NRSRO, unless noted otherwise. Moody’s Ratings was selected because it is recognized as a leading NRSRO that offers a transparent and reliable rating process for debt instruments. See Schedules of Portfolio Investments for individual bond ratings. Visit our website at www.dupree-funds.com/documents. |
| Updated Prospectus Web Address | www.dupree-funds.com/documents |
| Tennessee Tax-Free Short-to-Medium Series | |
| Shareholder Report [Line Items] | |
| Fund Name | Tennessee Tax-Free Short-to-Medium Series |
| Class Name | Tennessee Tax-Free Short-to-Medium Series |
| Trading Symbol | TTSMX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Tennessee Tax-Free Short-to-Medium |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the Fund at www.dupree-funds.com/documents. You can also request this information by contacting us at (800) 866-0614 |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | (800) 866-0614 |
| Additional Information Email | info@dupree-funds.com |
| Additional Information Website | www.dupree-funds.com/documents |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) The below table explains the costs that you would have paid within the reporting period. Fund (Class) Costs of a $10,000 investment Costs paid as a percentage of a Tennessee Tax-Free Short-to-Medium $ 70 0.70% |
| Expenses Paid, Amount | $ 70 |
| Expense Ratio, Percent | 0.70% |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year? During the reporting period, longer-dated, lower-rated municipal bonds generally outperformed shorter-date, higher-quality bonds. The Fund provided a total return of 1.81% during the reporting period which was lower than the Bloomberg Municipal Bond Index (the “Muni Index”) which returned 3.21%. The Fund’s underperformance was due primarily to the fact that it held fewer “BBB” rated bonds and had a substantially shorter duration than the Muni Index. During the reporting period, the Fund’s use of its current management strategy did not cause the Fund’s performance to deviate materially from the manager’s expectations. We do not plan to change the investment strategy of the Fund substantially in the upcoming year. |
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance is not a good predictor of the Fund’s future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total return values (as of June 30, 2024): 1 Year 5 Years 10 Years Tennessee Tax-Free Short-to-Medium 1.81 % 0.48 % 1.04 % Bloomberg Municipal Bond Index 3.21 % 1.16 % 2.39 % |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Net Assets | $ 2,832,241 |
| Holdings Count | Holding | 15 |
| Advisory Fees Paid, Amount | $ 0 |
| Investment Company, Portfolio Turnover | 12.62% |
| Additional Fund Statistics [Text Block] | What are the Key Fund statistics you should know? The following table outlines key Fund statistics that you should pay attention to: Fund’s net assets $ 2,832,241 Total number of portfolio holdings 15 Net advisory fees paid $ -0- Portfolio turnover rate as of the end of the reporting period 12.62% |
| Holdings [Text Block] | What is the Fund invested in? The tables and charts below show the investment makeup of the Fund, representing the percentage of total net assets of the Fund. Composition Credit Quality* Ratings have been assigned by a Nationally Recognized Statistical Rating Organizations (“NRSRO”). All ratings are by Moody’s Ratings, an NRSRO, unless noted otherwise. Moody’s Ratings was selected because it is recognized as a leading NRSRO that offers a transparent and reliable rating process for debt instruments. See Schedules of Portfolio Investments for individual bond ratings. Visit our website at www.dupree-funds.com/documents. |
| Updated Prospectus Web Address | www.dupree-funds.com/documents |
| Intermediate Government Bond Series | |
| Shareholder Report [Line Items] | |
| Fund Name | Intermediate Government Bond Series |
| Class Name | Intermediate Government Bond Series |
| Trading Symbol | DPIGX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Intermediate Government Bond Series (the “Fund”) for the period of July 1, 2023 to June 30, 2024 (the “reporting period”). |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the Fund at www.dupree-funds.com/documents. (800) 866-0614 |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | (800) 866-0614 |
| Additional Information Email | info@dupree-funds.com |
| Additional Information Website | www.dupree-funds.com/documents |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) The below table explains the costs that you would have paid within the reporting period. Fund (Class) Costs of a $10,000 investment Costs paid as a percentage of a Intermediate Government Bond Series $ 70 0.70% |
| Expenses Paid, Amount | $ 70 |
| Expense Ratio, Percent | 0.70% |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year? Yields increased across the taxable yield curve during the reporting period. Shorter-dated taxable bonds generally outperformed longer-dated bonds during the reporting period. The Fund provided a total return of 4.58% during the reporting period which was higher than the Bloomberg Intermediate Government Bond Index (“Gov Bond Index”) which returned 3.40%. The Fund’s outperformance was due primarily to the fact that it had a shorter duration than the Gov Bond Index. During the reporting period, the Fund’s use of its current management strategy did not cause the performance to deviate materially from the manager’s expectations. We do not plan to change the investment strategy of the Fund substantially in the upcoming year. |
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance is not a good predictor of the Fund’s future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total return values (as of June 30, 2024): 1 Year 5 Years 10 Years Intermediate Government Bond Series 4.58 % 1.18 % 1.72 % Bloomberg Intermediate U.S. Government Bond Index 3.40 % 0.29 % 1.11 % |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Net Assets | $ 9,698,809 |
| Holdings Count | Holding | 18 |
| Advisory Fees Paid, Amount | $ 900 |
| Investment Company, Portfolio Turnover | 26.47% |
| Additional Fund Statistics [Text Block] | What are the Key Fund statistics you should know? The following table outlines key Fund statistics that you should pay attention to: Fund’s net assets $ 9,698,809 Total number of portfolio holdings 18 Net advisory fees paid $ 900 Portfolio turnover rate as of the end of the reporting period 26.47% |
| Holdings [Text Block] | What is the Fund invested in? The tables and charts below show the investment makeup of the Fund, representing the percentage of total net assets of the Fund. Composition Credit Quality* Ratings have been assigned by a Nationally Recognized Statistical Rating Organizations (“NRSRO”). All ratings are by Moody’s Ratings, an NRSRO, unless noted otherwise. Moody’s Ratings was selected because it is recognized as a leading NRSRO that offers a transparent and reliable rating process for debt instruments. See Schedules of Portfolio Investments for individual bond ratings. Visit our website at www.dupree-funds.com/documents. |
| Updated Prospectus Web Address | www.dupree-funds.com/documents |
| Taxable Municipal Bond Series | |
| Shareholder Report [Line Items] | |
| Fund Name | Taxable Municipal Bond Series |
| Class Name | Taxable Municipal Bond Series |
| Trading Symbol | DUTMX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Taxable Municipal Bond Series (the “Fund”) for the period of July 1, 2023 to June 30, 2024 (the “reporting period”). |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the Fund at www.dupree-funds.com/documents . 866-0614 |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | (800) 866-0614 |
| Additional Information Email | info@dupree-funds.com |
| Additional Information Website | www.dupree-funds.com/documents |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) The below table explains the costs that you would have paid within the reporting period. Fund (Class) Costs of a $10,000 investment Costs paid as a percentage of a Taxable Municipal Bond Series $ 70 0.70% |
| Expenses Paid, Amount | $ 70 |
| Expense Ratio, Percent | 0.70% |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year? Yields increased across the taxable municipal yield curve during the reporting period. Shorter-dated, lower-rated taxable municipal bonds generally outperformed longer-dated, higher-rated bonds during the reporting period. The Fund provided a total return of 2.25% during the reporting period which was lower than the Bloomberg Taxable Municipal Bond Index (“Taxable Muni Index”) which returned 3.81%. The Fund’s underperformance was due primarily to the fact that it held fewer lower-rated credits and had a longer duration than the Taxable Muni Index. During the reporting period, the Fund’s use of its current investment strategy did not cause the performance to deviate materially from the manager’s expectations. We do not plan to change the investment strategy of the Fund substantially in the upcoming year. |
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance is not a good predictor of the Fund’s future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total return values (as of June 30, 2024): 1 Year 5 Years 10 Years Taxable Municipal Bond Series 2.25 % (2.63) % 0.98 % Bloomberg Taxable Municipal Bond Index 3.81 % 0.34 % 2.88 % |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Net Assets | $ 3,505,759 |
| Holdings Count | Holding | 19 |
| Advisory Fees Paid, Amount | $ 0 |
| Investment Company, Portfolio Turnover | 12.53% |
| Additional Fund Statistics [Text Block] | What are the Key Fund statistics you should know? The following table outlines key Fund statistics that you should pay attention to: Fund’s net assets $ 3,505,759 Total number of portfolio holdings 19 Net advisory fees paid $ -0- Portfolio turnover rate as of the end of the reporting period 12.53% |
| Holdings [Text Block] | What is the Fund invested in? The tables and charts below show the investment makeup of the Fund, representing the percentage of total net assets of the Fund. Composition Credit Quality* Ratings have been assigned by a Nationally Recognized Statistical Rating Organizations (“NRSRO”). All ratings are by Moody’s Ratings, an NRSRO, unless noted otherwise. Moody’s Ratings was selected because it is recognized as a leading NRSRO that offers a transparent and reliable rating process for debt instruments. See Schedules of Portfolio Investments for individual bond ratings. Visit our website at www.dupree-funds.com/documents. |
| Updated Prospectus Web Address | www.dupree-funds.com/documents |
| Shareholder Report, Line Graph (Details) - USD ($) | 12 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Taxable Municipal Bond Series | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | Taxable Municipal Bond Series | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 10,986 | $ 10,244 | $ 13,708 | $ 13,603 | $ 12,807 | $ 12,011 | $ 11,772 | $ 11,201 | $ 10,763 | $ 10,545 | $ 10,566 | $ 10,303 | $ 13,876 | $ 13,533 | $ 12,856 | $ 11,818 | $ 11,690 | $ 11,177 | $ 10,749 | $ 10,415 | $ 10,080 | $ 9,892 | $ 13,765 | $ 13,301 | $ 12,844 | $ 11,746 | $ 11,654 | $ 11,407 | $ 10,707 | $ 10,289 | $ 10,257 | $ 10,212 | $ 13,639 | $ 13,426 | $ 12,843 | $ 11,835 | $ 11,606 | $ 11,518 | $ 10,695 | $ 10,218 | $ 10,621 | $ 10,793 | $ 13,808 | $ 13,370 | $ 12,956 | $ 11,879 | $ 11,637 | $ 11,517 | $ 10,604 | $ 10,235 | $ 10,652 | $ 11,098 | $ 13,817 | $ 13,401 | $ 12,625 | $ 11,772 | $ 11,535 | $ 11,515 | $ 10,611 | $ 10,023 | $ 11,026 | $ 10,784 | $ 11,047 | $ 13,614 | $ 13,254 | $ 12,599 | $ 11,815 | $ 11,509 | $ 11,420 | $ 10,449 | $ 10,000 | $ 10,869 | $ 10,788 | $ 11,052 | $ 13,399 | $ 13,134 | $ 12,514 | $ 11,813 | $ 11,485 | $ 11,160 | $ 10,645 | $ 10,664 | $ 10,862 | $ 11,705 | $ 13,340 | $ 13,083 | $ 12,246 | $ 11,740 | $ 11,384 | $ 11,096 | $ 10,612 | $ 11,036 | $ 10,766 | $ 12,606 | $ 13,086 | $ 12,995 | $ 12,256 | $ 11,795 | $ 11,327 | $ 11,085 | $ 10,678 | $ 10,905 | $ 10,529 | $ 13,247 | $ 13,329 | $ 13,295 | $ 12,037 | $ 11,676 | $ 11,345 | $ 11,041 | $ 10,615 | $ 11,012 | $ 10,731 | $ 13,351 | $ 13,534 | $ 13,046 | $ 12,051 | $ 11,687 | $ 11,227 | $ 10,958 | $ 10,771 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intermediate Government Bond Series | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | Intermediate Government Bond Series | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 11,861 | $ 11,804 | $ 11,735 | $ 11,740 | $ 11,695 | $ 11,715 | $ 11,670 | $ 11,540 | $ 11,424 | $ 11,382 | $ 11,401 | $ 11,359 | $ 11,341 | $ 11,336 | $ 11,367 | $ 11,339 | $ 11,176 | $ 11,269 | $ 11,204 | $ 11,175 | $ 11,078 | $ 11,104 | $ 11,259 | $ 11,354 | $ 11,296 | $ 11,334 | $ 11,335 | $ 11,407 | $ 11,513 | $ 11,551 | $ 11,610 | $ 11,623 | $ 11,624 | $ 11,649 | $ 11,685 | $ 11,698 | $ 11,676 | $ 11,678 | $ 11,667 | $ 11,657 | $ 11,692 | $ 11,728 | $ 11,740 | $ 11,730 | $ 11,731 | $ 11,753 | $ 11,755 | $ 11,755 | $ 11,733 | $ 11,734 | $ 11,700 | $ 11,668 | $ 11,555 | $ 11,388 | $ 11,298 | $ 11,287 | $ 11,332 | $ 11,287 | $ 11,310 | $ 11,177 | $ 11,187 | $ 11,132 | $ 10,988 | $ 10,988 | $ 10,867 | $ 10,857 | $ 10,811 | $ 10,669 | $ 10,614 | $ 10,635 | $ 10,678 | $ 10,601 | $ 10,643 | $ 10,663 | $ 10,576 | $ 10,661 | $ 10,617 | $ 10,638 | $ 10,764 | $ 10,762 | $ 10,772 | $ 10,791 | $ 10,864 | $ 10,799 | $ 10,755 | $ 10,796 | $ 10,741 | $ 10,667 | $ 10,685 | $ 10,644 | $ 10,621 | $ 10,639 | $ 10,897 | $ 10,967 | $ 10,925 | $ 10,985 | $ 10,973 | $ 10,757 | $ 10,765 | $ 10,775 | $ 10,783 | $ 10,691 | $ 10,436 | $ 10,454 | $ 10,493 | $ 10,552 | $ 10,420 | $ 10,388 | $ 10,296 | $ 10,425 | $ 10,423 | $ 10,471 | $ 10,390 | $ 10,568 | $ 10,259 | $ 10,266 | $ 10,166 | $ 10,066 | $ 10,143 | $ 9,993 | $ 10,000 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Tennessee Tax-Free Short-to-Medium Series | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | Tennessee Tax-Free Short-to-Medium Series | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 11,085 | 11,014 | 11,029 | 11,056 | 11,082 | 11,077 | 11,103 | 11,011 | 10,792 | 10,786 | 10,877 | 10,904 | 10,888 | 10,841 | 10,910 | 10,947 | 10,815 | 10,971 | 10,841 | 10,816 | 10,634 | 10,651 | 10,837 | 10,980 | 10,850 | 10,868 | 10,748 | 10,859 | 11,042 | 11,082 | 11,265 | 11,261 | 11,236 | 11,273 | 11,310 | 11,336 | 11,290 | 11,296 | 11,292 | 11,248 | 11,213 | 11,323 | 11,298 | 11,293 | 11,248 | 11,264 | 11,259 | 11,295 | 11,199 | 11,215 | 10,947 | 10,963 | 11,139 | 11,075 | 10,948 | 10,923 | 10,909 | 10,894 | 10,990 | 10,896 | 10,821 | 10,776 | 10,672 | 10,678 | 10,604 | 10,551 | 10,477 | 10,384 | 10,301 | 10,337 | 10,383 | 10,380 | 10,357 | 10,345 | 10,273 | 10,310 | 10,317 | 10,335 | 10,380 | 10,337 | 10,412 | 10,417 | 10,451 | 10,418 | 10,374 | 10,409 | 10,337 | 10,295 | 10,290 | 10,247 | 10,204 | 10,151 | 10,358 | 10,401 | 10,436 | 10,443 | 10,430 | 10,351 | 10,376 | 10,344 | 10,359 | 10,338 | 10,250 | 10,237 | 10,234 | 10,212 | 10,153 | 10,140 | 10,099 | 10,086 | 10,119 | 10,143 | 10,129 | 10,201 | 10,075 | 10,079 | 10,084 | 10,061 | 10,075 | 10,014 | 10,000 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Tennessee Tax-Free Income Series | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | Tennessee Tax-Free Income Series | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 11,937 | 11,916 | 11,940 | 11,154 | 11,610 | 11,623 | 11,421 | 11,025 | 11,406 | 11,699 | 12,289 | 12,221 | 12,254 | 12,110 | 12,153 | 12,017 | 11,916 | 11,724 | 11,685 | 11,645 | 11,483 | 11,301 | 11,031 | 10,889 | 10,923 | 10,870 | 10,999 | 10,915 | 10,822 | 10,661 | 10,577 | 10,871 | 10,934 | 10,702 | 10,560 | 10,418 | 10,277 | 10,376 | 10,316 | 10,166 | 10,000 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| North Carolina Tax-Free Short-to-Medium Series | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | North Carolina Tax-Free Short-to-Medium Series | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 10,971 | 10,901 | 10,926 | 10,961 | 10,976 | 10,980 | 11,005 | 10,914 | 10,645 | 10,649 | 10,758 | 10,804 | 10,787 | 10,740 | 10,827 | 10,873 | 10,722 | 10,893 | 10,733 | 10,696 | 10,475 | 10,491 | 10,733 | 10,893 | 10,735 | 10,783 | 10,646 | 10,795 | 11,024 | 11,052 | 11,261 | 11,257 | 11,223 | 11,249 | 11,296 | 11,321 | 11,267 | 11,273 | 11,268 | 11,213 | 11,188 | 11,274 | 11,269 | 11,253 | 11,189 | 11,204 | 11,200 | 11,225 | 11,120 | 11,135 | 10,902 | 10,907 | 11,129 | 11,046 | 10,914 | 10,889 | 10,866 | 10,861 | 10,956 | 10,854 | 10,772 | 10,728 | 10,607 | 10,613 | 10,521 | 10,469 | 10,387 | 10,276 | 10,176 | 10,221 | 10,276 | 10,263 | 10,240 | 10,228 | 10,148 | 10,183 | 10,189 | 10,226 | 10,310 | 10,249 | 10,332 | 10,328 | 10,381 | 10,339 | 10,287 | 10,330 | 10,232 | 10,171 | 10,149 | 10,108 | 10,058 | 9,998 | 10,238 | 10,291 | 10,326 | 10,333 | 10,321 | 10,235 | 10,259 | 10,228 | 10,242 | 10,229 | 10,160 | 10,146 | 10,152 | 10,138 | 10,097 | 10,092 | 10,060 | 10,047 | 10,060 | 10,083 | 10,077 | 10,128 | 10,041 | 10,054 | 10,049 | 10,025 | 10,048 | 10,006 | 10,000 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| North Carolina Tax-Free Income Series | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | North Carolina Tax-Free Income Series | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 11,963 | 11,943 | 11,958 | 11,184 | 11,627 | 11,666 | 11,406 | 10,932 | 11,399 | 11,811 | 12,580 | 12,486 | 12,528 | 12,351 | 12,431 | 12,233 | 12,149 | 11,901 | 11,835 | 11,807 | 11,628 | 11,409 | 11,131 | 10,969 | 11,003 | 10,949 | 11,107 | 10,986 | 10,865 | 10,706 | 10,614 | 10,957 | 11,050 | 10,757 | 10,608 | 10,467 | 10,300 | 10,392 | 10,325 | 10,158 | 10,000 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Mississippi Tax-Free Income Series | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | Mississippi Tax-Free Income Series | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 12,111 | 12,094 | 12,143 | 11,451 | 11,804 | 11,837 | 11,642 | 11,243 | 11,669 | 11,987 | 12,648 | 12,563 | 12,609 | 12,460 | 12,482 | 12,339 | 12,280 | 12,039 | 11,994 | 11,951 | 11,806 | 11,613 | 11,334 | 11,169 | 11,213 | 11,155 | 11,301 | 11,216 | 11,103 | 10,908 | 10,805 | 11,101 | 11,157 | 10,901 | 10,734 | 10,563 | 10,380 | 10,497 | 10,386 | 10,205 | 10,000 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Kentucky Tax-Free Short-to-Medium Series | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | Kentucky Tax-Free Short-to-Medium Series | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 11,217 | 11,132 | 11,178 | 11,225 | 11,227 | 11,230 | 11,255 | 11,149 | 10,870 | 10,873 | 10,986 | 11,033 | 11,016 | 10,957 | 11,026 | 11,053 | 10,908 | 11,065 | 10,921 | 10,905 | 10,676 | 10,682 | 10,880 | 11,013 | 10,892 | 10,919 | 10,819 | 10,932 | 11,107 | 11,136 | 11,311 | 11,296 | 11,282 | 11,310 | 11,337 | 11,364 | 11,328 | 11,334 | 11,317 | 11,281 | 11,265 | 11,292 | 11,297 | 11,281 | 11,245 | 11,250 | 11,235 | 11,260 | 11,121 | 11,126 | 10,885 | 10,931 | 11,139 | 11,084 | 10,966 | 10,930 | 10,915 | 10,900 | 10,986 | 10,910 | 10,833 | 10,777 | 10,680 | 10,684 | 10,607 | 10,552 | 10,476 | 10,380 | 10,304 | 10,328 | 10,392 | 10,377 | 10,361 | 10,326 | 10,251 | 10,294 | 10,298 | 10,344 | 10,387 | 10,332 | 10,435 | 10,440 | 10,523 | 10,469 | 10,394 | 10,438 | 10,325 | 10,251 | 10,235 | 10,182 | 10,128 | 10,055 | 10,367 | 10,428 | 10,452 | 10,437 | 10,440 | 10,348 | 10,370 | 10,316 | 10,318 | 10,321 | 10,210 | 10,174 | 10,177 | 10,159 | 10,105 | 10,087 | 10,050 | 10,051 | 10,090 | 10,110 | 10,092 | 10,131 | 10,056 | 10,055 | 10,056 | 10,037 | 10,056 | 10,019 | 10,000 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Kentucky Tax-Free Income Series | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | Kentucky Tax-Free Income Series | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 12,130 | 12,132 | 12,151 | 11,292 | 11,774 | 11,777 | 11,555 | 11,092 | 11,503 | 11,894 | 12,584 | 12,482 | 12,519 | 12,335 | 12,354 | 12,179 | 11,965 | 11,872 | 11,839 | 11,790 | 11,607 | 11,381 | 11,096 | 10,908 | 10,927 | 10,860 | 10,992 | 10,908 | 10,827 | 10,662 | 10,553 | 10,849 | 10,903 | 10,686 | 10,523 | 10,398 | 10,262 | 10,347 | 10,264 | 10,148 | 10,000 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Alabama Tax-Free Income Series | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | Alabama Tax-Free Income Series | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 12,224 | 12,207 | 12,257 | 11,382 | 11,848 | 11,919 | 11,682 | 11,244 | 11,722 | 12,066 | 12,792 | 12,693 | 12,745 | 12,559 | 12,628 | 12,456 | 12,382 | 12,105 | 11,999 | 11,930 | 11,738 | 11,490 | 11,198 | 11,045 | 11,094 | 11,030 | 11,149 | 11,049 | 10,958 | 10,806 | 10,707 | 10,982 | 11,049 | 10,786 | 10,650 | 10,507 | 10,364 | 10,455 | 10,373 | 10,190 | 10,000 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Bloomberg Taxable Municipal Index [Member] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 13,294 | $ 12,214 | $ 14,916 | $ 14,777 | $ 13,371 | $ 12,038 | $ 11,963 | $ 11,061 | $ 10,574 | $ 10,465 | $ 12,665 | $ 12,268 | $ 15,051 | $ 14,619 | $ 13,466 | $ 11,770 | $ 11,870 | $ 11,062 | $ 10,564 | $ 10,364 | $ 12,069 | $ 11,740 | $ 14,909 | $ 14,345 | $ 13,497 | $ 11,673 | $ 11,835 | $ 11,469 | $ 10,504 | $ 10,225 | $ 12,321 | $ 12,040 | $ 14,851 | $ 14,570 | $ 13,498 | $ 11,793 | $ 11,781 | $ 11,662 | $ 10,502 | $ 10,086 | $ 12,687 | $ 12,702 | $ 15,038 | $ 14,513 | $ 13,688 | $ 11,906 | $ 11,879 | $ 11,718 | $ 10,408 | $ 10,241 | $ 12,738 | $ 13,079 | $ 15,066 | $ 14,679 | $ 13,095 | $ 11,799 | $ 11,649 | $ 11,761 | $ 10,428 | $ 10,016 | $ 13,283 | $ 12,795 | $ 12,832 | $ 14,822 | $ 14,325 | $ 13,057 | $ 11,842 | $ 11,536 | $ 11,605 | $ 10,296 | $ 10,000 | $ 13,145 | $ 12,821 | $ 12,858 | $ 14,577 | $ 13,912 | $ 12,918 | $ 11,829 | $ 11,489 | $ 11,283 | $ 10,487 | $ 12,921 | $ 13,008 | $ 12,948 | $ 14,481 | $ 13,747 | $ 12,491 | $ 11,724 | $ 11,348 | $ 11,104 | $ 10,565 | $ 13,307 | $ 12,850 | $ 13,680 | $ 14,264 | $ 13,528 | $ 12,495 | $ 11,840 | $ 11,248 | $ 11,055 | $ 10,698 | $ 13,137 | $ 12,539 | $ 14,405 | $ 14,486 | $ 14,424 | $ 12,119 | $ 11,682 | $ 11,266 | $ 10,987 | $ 10,636 | $ 13,286 | $ 12,830 | $ 14,538 | $ 14,774 | $ 13,930 | $ 12,127 | $ 11,795 | $ 11,138 | $ 10,856 | $ 10,851 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Bloomberg Intermediate U.S. Government Bond Index [Member] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | Bloomberg Intermediate U.S. Government Bond Index | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 11,185 | $ 11,091 | $ 10,969 | 11,120 | $ 11,065 | $ 11,183 | 11,159 | $ 10,931 | $ 10,697 | 10,732 | $ 10,835 | $ 10,829 | 10,817 | $ 10,917 | $ 10,998 | 10,940 | $ 10,680 | $ 10,869 | 10,698 | $ 10,724 | $ 10,543 | 10,591 | $ 10,849 | $ 11,070 | 10,925 | $ 11,006 | $ 10,932 | 11,109 | $ 11,395 | $ 11,447 | 11,594 | $ 11,625 | $ 11,596 | 11,662 | $ 11,733 | $ 11,752 | 11,662 | $ 11,671 | $ 11,634 | 11,591 | $ 11,670 | $ 11,767 | 11,794 | $ 11,791 | $ 11,776 | 11,820 | $ 11,811 | $ 11,834 | 11,797 | $ 11,786 | $ 11,765 | 11,733 | $ 11,498 | $ 11,312 | 11,155 | $ 11,158 | $ 11,185 | 11,153 | $ 11,202 | $ 11,004 | 11,023 | $ 10,933 | $ 10,776 | 10,771 | $ 10,641 | $ 10,649 | 10,603 | $ 10,448 | $ 10,377 | 10,373 | $ 10,426 | $ 10,364 | 10,384 | $ 10,386 | $ 10,319 | 10,378 | $ 10,324 | $ 10,355 | 10,454 | $ 10,451 | $ 10,483 | 10,497 | $ 10,558 | $ 10,494 | 10,461 | $ 10,488 | $ 10,447 | 10,393 | $ 10,387 | $ 10,357 | 10,337 | $ 10,340 | $ 10,516 | 10,567 | $ 10,549 | $ 10,596 | 10,592 | $ 10,444 | $ 10,459 | 10,462 | $ 10,443 | $ 10,391 | 10,229 | $ 10,248 | $ 10,282 | 10,315 | $ 10,239 | $ 10,233 | 10,192 | $ 10,232 | $ 10,227 | 10,236 | $ 10,182 | $ 10,271 | 10,110 | $ 10,136 | $ 10,085 | 10,015 | $ 10,049 | $ 9,988 | 10,000 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Bloomberg Municipal Bond Index [Member] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value [Line Items] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Line Graph and Table Measure Name | Bloomberg Municipal Bond Index | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Account Value | $ 12,677 | $ 12,679 | $ 12,728 | $ 11,797 | $ 12,283 | $ 12,295 | $ 11,963 | $ 11,491 | $ 11,903 | $ 12,264 | $ 13,078 | $ 12,985 | $ 13,019 | $ 12,837 | $ 12,882 | $ 12,652 | $ 12,490 | $ 12,159 | $ 12,236 | $ 12,146 | $ 11,958 | $ 11,708 | $ 11,378 | $ 11,190 | $ 11,207 | $ 11,110 | $ 11,234 | $ 11,151 | $ 11,034 | $ 10,822 | $ 10,654 | $ 11,054 | $ 11,088 | $ 10,806 | $ 10,628 | $ 10,470 | $ 10,300 | $ 10,392 | $ 10,288 | $ 10,149 | $ 10,000 |
| Shareholder Report, Average Annual Return (Details) | 12 Months Ended | 60 Months Ended | 120 Months Ended |
| Jun. 30, 2024 | Jun. 30, 2024 | Jun. 30, 2024 | |
| Taxable Municipal Bond Series | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Taxable Municipal Bond Series | ||
| Average Annual Return, Percent | 2.25% | (2.63%) | 0.98% |
| Intermediate Government Bond Series | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Intermediate Government Bond Series | ||
| Average Annual Return, Percent | 4.58% | 1.18% | 1.72% |
| Tennessee Tax-Free Short-to-Medium Series | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Tennessee Tax-Free Short-to-Medium Series | ||
| Average Annual Return, Percent | 1.81% | 0.48% | 1.04% |
| Tennessee Tax-Free Income Series | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Tennessee Tax-Free Income Series | ||
| Average Annual Return, Percent | 2.82% | 0.78% | 1.79% |
| North Carolina Tax-Free Short-to-Medium Series | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | North Carolina Tax-Free Short-to-Medium Series | ||
| Average Annual Return, Percent | 1.71% | 0.37% | 0.93% |
| North Carolina Tax-Free Income Series | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | North Carolina Tax-Free Income Series | ||
| Average Annual Return, Percent | 2.89% | 0.57% | 1.81% |
| Mississippi Tax-Free Income Series | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Mississippi Tax-Free Income Series | ||
| Average Annual Return, Percent | 2.60% | 0.51% | 1.93% |
| Kentucky Tax-Free Short-to-Medium Series | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Kentucky Tax-Free Short-to-Medium Series | ||
| Average Annual Return, Percent | 1.83% | 0.70% | 1.16% |
| Kentucky Tax-Free Income Series | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Kentucky Tax-Free Income Series | ||
| Average Annual Return, Percent | 3.03% | 0.88% | 1.95% |
| Alabama Tax-Free Income Series | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Alabama Tax-Free Income Series | ||
| Average Annual Return, Percent | 3.17% | 0.82% | 2.03% |
| Bloomberg Taxable Municipal Bond Index [Member] | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Bloomberg Taxable Municipal Bond Index | ||
| Average Annual Return, Percent | 3.81% | 0.34% | 2.88% |
| Bloomberg Intermediate U.S. Government Bond Index [Member] | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Bloomberg Intermediate U.S. Government Bond Index | ||
| Average Annual Return, Percent | 3.40% | 0.29% | 1.11% |
| Bloomberg Municipal Bond Index [Member] | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Bloomberg Municipal Bond Index | ||
| Average Annual Return, Percent | 3.21% | 1.16% | 2.39% |
| Shareholder Report, Holdings (Details) | Jun. 30, 2024 |
| Alabama Tax-Free Income Series | AaaAAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.98% |
| Alabama Tax-Free Income Series | AaAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 87.70% |
| Alabama Tax-Free Income Series | A [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.11% |
| Alabama Tax-Free Income Series | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.21% |
| Alabama Tax-Free Income Series | Liabilities in excess of assets [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | (1.79%) |
| Alabama Tax-Free Income Series | Hospital and Healthcare Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.70% |
| Alabama Tax-Free Income Series | Refunding [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.80% |
| Alabama Tax-Free Income Series | Miscellaneous Public Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.79% |
| Alabama Tax-Free Income Series | State and Local Mortgage/Housing Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.10% |
| Alabama Tax-Free Income Series | Municipal Utility Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.44% |
| Alabama Tax-Free Income Series | University Consolidated Education and Building Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 15.85% |
| Alabama Tax-Free Income Series | Prerefunded [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 15.97% |
| Alabama Tax-Free Income Series | Public Facilities Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 19.29% |
| Alabama Tax-Free Income Series | School Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 20.85% |
| Kentucky Tax-Free Income Series | AaaAAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.66% |
| Kentucky Tax-Free Income Series | AaAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 75.17% |
| Kentucky Tax-Free Income Series | A [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21.87% |
| Kentucky Tax-Free Income Series | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Kentucky Tax-Free Income Series | Hospital and Healthcare Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.08% |
| Kentucky Tax-Free Income Series | Refunding [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.22% |
| Kentucky Tax-Free Income Series | Miscellaneous Public Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 35.01% |
| Kentucky Tax-Free Income Series | State and Local Mortgage/Housing Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.64% |
| Kentucky Tax-Free Income Series | Municipal Utility Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.18% |
| Kentucky Tax-Free Income Series | University Consolidated Education and Building Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 13.82% |
| Kentucky Tax-Free Income Series | Prerefunded [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.35% |
| Kentucky Tax-Free Income Series | Public Facilities Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.02% |
| Kentucky Tax-Free Income Series | School Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 24.31% |
| Kentucky Tax-Free Income Series | Other Assets Less Liabilities [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.79% |
| Kentucky Tax-Free Income Series | Ad Valorem Property [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.35% |
| Kentucky Tax-Free Income Series | Airport Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| Kentucky Tax-Free Income Series | Turnpikes/Toll Roads/Highway Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.53% |
| Kentucky Tax-Free Short-to-Medium Series | AaaAAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.33% |
| Kentucky Tax-Free Short-to-Medium Series | AaAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 62.96% |
| Kentucky Tax-Free Short-to-Medium Series | A [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 30.71% |
| Kentucky Tax-Free Short-to-Medium Series | Hospital and Healthcare Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.22% |
| Kentucky Tax-Free Short-to-Medium Series | Refunding [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.82% |
| Kentucky Tax-Free Short-to-Medium Series | Miscellaneous Public Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.06% |
| Kentucky Tax-Free Short-to-Medium Series | State and Local Mortgage/Housing Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.18% |
| Kentucky Tax-Free Short-to-Medium Series | Municipal Utility Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 9.04% |
| Kentucky Tax-Free Short-to-Medium Series | University Consolidated Education and Building Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 9.55% |
| Kentucky Tax-Free Short-to-Medium Series | Public Facilities Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 16.14% |
| Kentucky Tax-Free Short-to-Medium Series | School Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 20.34% |
| Kentucky Tax-Free Short-to-Medium Series | Other Assets Less Liabilities [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.31% |
| Kentucky Tax-Free Short-to-Medium Series | Ad Valorem Property [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.06% |
| Kentucky Tax-Free Short-to-Medium Series | Airport Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.62% |
| Kentucky Tax-Free Short-to-Medium Series | Turnpikes/Toll Roads/Highway Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 14.66% |
| Mississippi Tax-Free Income Series | AaaAAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.56% |
| Mississippi Tax-Free Income Series | AaAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 87.42% |
| Mississippi Tax-Free Income Series | A [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.02% |
| Mississippi Tax-Free Income Series | Liabilities in excess of assets [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | (1.60%) |
| Mississippi Tax-Free Income Series | Hospital and Healthcare Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.37% |
| Mississippi Tax-Free Income Series | Refunding [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.59% |
| Mississippi Tax-Free Income Series | Miscellaneous Public Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 14.11% |
| Mississippi Tax-Free Income Series | State and Local Mortgage/Housing Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.68% |
| Mississippi Tax-Free Income Series | Municipal Utility Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.60% |
| Mississippi Tax-Free Income Series | University Consolidated Education and Building Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 26.89% |
| Mississippi Tax-Free Income Series | Prerefunded [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.23% |
| Mississippi Tax-Free Income Series | Public Facilities Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.90% |
| Mississippi Tax-Free Income Series | School Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.76% |
| Mississippi Tax-Free Income Series | Turnpikes/Toll Roads/Highway Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.03% |
| Mississippi Tax-Free Income Series | Lease Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.44% |
| North Carolina Tax-Free Income Series | AaaAAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.51% |
| North Carolina Tax-Free Income Series | AaAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 78.78% |
| North Carolina Tax-Free Income Series | A [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 13.28% |
| North Carolina Tax-Free Income Series | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.40% |
| North Carolina Tax-Free Income Series | Baa2 [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.03% |
| North Carolina Tax-Free Income Series | Hospital and Healthcare Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.13% |
| North Carolina Tax-Free Income Series | Refunding [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.17% |
| North Carolina Tax-Free Income Series | Miscellaneous Public Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.91% |
| North Carolina Tax-Free Income Series | State and Local Mortgage/Housing Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.50% |
| North Carolina Tax-Free Income Series | Municipal Utility Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 15.56% |
| North Carolina Tax-Free Income Series | University Consolidated Education and Building Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.76% |
| North Carolina Tax-Free Income Series | Prerefunded [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.54% |
| North Carolina Tax-Free Income Series | Public Facilities Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 13.84% |
| North Carolina Tax-Free Income Series | School Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21.69% |
| North Carolina Tax-Free Income Series | Other Assets Less Liabilities [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.70% |
| North Carolina Tax-Free Income Series | Airport Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.68% |
| North Carolina Tax-Free Income Series | Turnpikes/Toll Roads/Highway Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.52% |
| North Carolina Tax-Free Short-to-Medium Series | AaaAAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.70% |
| North Carolina Tax-Free Short-to-Medium Series | AaAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 60.15% |
| North Carolina Tax-Free Short-to-Medium Series | A [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 29.32% |
| North Carolina Tax-Free Short-to-Medium Series | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.83% |
| North Carolina Tax-Free Short-to-Medium Series | Hospital and Healthcare Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.56% |
| North Carolina Tax-Free Short-to-Medium Series | Refunding [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.99% |
| North Carolina Tax-Free Short-to-Medium Series | Miscellaneous Public Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.61% |
| North Carolina Tax-Free Short-to-Medium Series | Municipal Utility Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 14.79% |
| North Carolina Tax-Free Short-to-Medium Series | University Consolidated Education and Building Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 34.77% |
| North Carolina Tax-Free Short-to-Medium Series | Prerefunded [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.79% |
| North Carolina Tax-Free Short-to-Medium Series | Public Facilities Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.64% |
| North Carolina Tax-Free Short-to-Medium Series | School Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.18% |
| North Carolina Tax-Free Short-to-Medium Series | Other Assets Less Liabilities [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.48% |
| North Carolina Tax-Free Short-to-Medium Series | Turnpikes/Toll Roads/Highway Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 9.98% |
| North Carolina Tax-Free Short-to-Medium Series | Lease Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.21% |
| Tennessee Tax-Free Income Series | AaaAAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.87% |
| Tennessee Tax-Free Income Series | AaAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 76.23% |
| Tennessee Tax-Free Income Series | A [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21.90% |
| Tennessee Tax-Free Income Series | Hospital and Healthcare Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.73% |
| Tennessee Tax-Free Income Series | Refunding [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.43% |
| Tennessee Tax-Free Income Series | Miscellaneous Public Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.59% |
| Tennessee Tax-Free Income Series | State and Local Mortgage/Housing Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.79% |
| Tennessee Tax-Free Income Series | Municipal Utility Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 38.74% |
| Tennessee Tax-Free Income Series | University Consolidated Education and Building Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.30% |
| Tennessee Tax-Free Income Series | Prerefunded [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.08% |
| Tennessee Tax-Free Income Series | Public Facilities Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 9.10% |
| Tennessee Tax-Free Income Series | School Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 13.10% |
| Tennessee Tax-Free Income Series | Other Assets Less Liabilities [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.84% |
| Tennessee Tax-Free Income Series | Airport Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.30% |
| Tennessee Tax-Free Short-to-Medium Series | AaAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 88.26% |
| Tennessee Tax-Free Short-to-Medium Series | Aa/AA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.74% |
| Tennessee Tax-Free Short-to-Medium Series | Refunding [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 33.74% |
| Tennessee Tax-Free Short-to-Medium Series | Miscellaneous Public Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.24% |
| Tennessee Tax-Free Short-to-Medium Series | Municipal Utility Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 37.30% |
| Tennessee Tax-Free Short-to-Medium Series | University Consolidated Education and Building Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.55% |
| Tennessee Tax-Free Short-to-Medium Series | School Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 14.56% |
| Tennessee Tax-Free Short-to-Medium Series | Other Assets Less Liabilities [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.61% |
| Intermediate Government Bond Series | AaaAAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 100% |
| Intermediate Government Bond Series | Other Assets Less Liabilities [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.24% |
| Intermediate Government Bond Series | Federal National Mortgage Corporation [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.14% |
| Intermediate Government Bond Series | Federal Farm Credit [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 9.60% |
| Intermediate Government Bond Series | Federal Home Loan Mortgage Corporation [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.29% |
| Intermediate Government Bond Series | Federal Home Loan Bank [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 69.73% |
| Taxable Municipal Bond Series | AaAA [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 96.29% |
| Taxable Municipal Bond Series | A [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3% |
| Taxable Municipal Bond Series | Not Rated [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.71% |
| Taxable Municipal Bond Series | Hospital and Healthcare Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.72% |
| Taxable Municipal Bond Series | Miscellaneous Public Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.58% |
| Taxable Municipal Bond Series | State and Local Mortgage/Housing Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 9.39% |
| Taxable Municipal Bond Series | Municipal Utility Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 22.73% |
| Taxable Municipal Bond Series | University Consolidated Education and Building Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.98% |
| Taxable Municipal Bond Series | Prerefunded [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.69% |
| Taxable Municipal Bond Series | Public Facilities Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 16.99% |
| Taxable Municipal Bond Series | School Improvement [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.56% |
| Taxable Municipal Bond Series | Other Assets Less Liabilities [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.45% |
| Taxable Municipal Bond Series | Airport Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.44% |
| Taxable Municipal Bond Series | Turnpikes/Toll Roads/Highway Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 9.73% |
| Taxable Municipal Bond Series | Marina/Port Authority Revenue [Member] | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.74% |
