Shareholder Report, Average Annual Return (Details)
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12 Months Ended |
60 Months Ended |
120 Months Ended |
May 31, 2025 |
May 31, 2025 |
May 31, 2025 |
| C000001498 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at maximum sales charge (Offering Price)
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| Average Annual Return, Percent |
(3.74%)
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(0.73%)
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1.31%
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| C000001501 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class I Shares at NAV
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| Average Annual Return, Percent |
0.68%
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0.31%
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1.93%
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| C000001497 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class I Shares at NAV
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| Average Annual Return, Percent |
0.04%
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0.24%
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2.02%
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| C000001490 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at maximum sales charge (Offering Price)
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| Average Annual Return, Percent |
(3.39%)
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(0.68%)
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1.26%
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| C000001493 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class I Shares at NAV
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| Average Annual Return, Percent |
0.97%
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0.38%
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1.90%
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| C000001494 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at maximum sales charge (Offering Price)
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| Average Annual Return, Percent |
(4.37%)
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(0.81%)
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1.38%
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| C000001489 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class I Shares at NAV
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| Average Annual Return, Percent |
1.29%
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0.66%
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1.96%
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| C000001486 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at maximum sales charge (Offering Price)
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| Average Annual Return, Percent |
(3.08%)
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(0.39%)
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1.33%
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| C000001474 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at maximum sales charge (Offering Price)
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| Average Annual Return, Percent |
(3.64%)
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(0.72%)
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1.34%
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| C000001477 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class I Shares at NAV
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| Average Annual Return, Percent |
0.79%
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0.31%
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1.98%
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| C000001478 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at maximum sales charge (Offering Price)
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| Average Annual Return, Percent |
(3.39%)
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(0.72%)
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1.53%
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| C000001481 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class I Shares at NAV
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| Average Annual Return, Percent |
1.06%
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0.32%
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2.17%
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| Without Sales Load [Member] | C000001498 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
0.51%
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0.12%
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1.74%
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| Without Sales Load [Member] | C000137698 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class C Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
(0.31%)
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(0.68%)
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1.09%
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| Without Sales Load [Member] | C000137697 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class C Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
(0.96%)
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(0.74%)
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1.17%
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| Without Sales Load [Member] | C000001490 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
0.87%
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0.18%
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1.70%
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| Without Sales Load [Member] | C000137696 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class C Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
0.08%
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(0.61%)
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1.05%
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| Without Sales Load [Member] | C000001494 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
(0.14%)
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0.05%
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1.82%
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| Without Sales Load [Member] | C000137695 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class C Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
0.37%
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(0.33%)
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1.12%
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| Without Sales Load [Member] | C000001486 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
1.21%
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0.47%
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1.76%
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| Without Sales Load [Member] | C000001474 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
0.60%
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0.13%
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1.78%
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| Without Sales Load [Member] | C000137693 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class C Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
(0.32%)
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(0.70%)
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1.12%
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| Without Sales Load [Member] | C000001478 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class A Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
0.88%
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0.13%
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1.97%
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| Without Sales Load [Member] | C000137694 [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Class C Shares at NAV (excluding maximum sales charge)
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| Average Annual Return, Percent |
0.04%
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(0.69%)
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1.32%
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| S And P Municipal Bond Index [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
S&P Municipal Bond Index
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| Average Annual Return, Percent |
2.44%
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0.78%
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2.22%
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| Lipper Virginia Municipal Debt Funds Classification Average [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Lipper Virginia Municipal Debt Funds Classification Average
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| Average Annual Return, Percent |
0.71%
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(0.03%)
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1.32%
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| S And P Municipal Bond Virginia Index [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
S&P Municipal Bond Virginia Index
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| Average Annual Return, Percent |
2.57%
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0.46%
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2.07%
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| S And P Municipal Bond Pennsylvania Index [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
S&P Municipal Bond Pennsylvania Index
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| Average Annual Return, Percent |
2.78%
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0.81%
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2.33%
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| Lipper Pennsylvania Municipal Debt Funds Classification Average [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Lipper Pennsylvania Municipal Debt Funds Classification Average
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| Average Annual Return, Percent |
1.18%
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0.39%
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1.71%
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| S And P Municipal Bond New Mexico Index [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
S&P Municipal Bond New Mexico Index
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| Average Annual Return, Percent |
3.86%
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0.79%
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1.91%
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| Lipper Other States Municipal Debt Funds Classification Average [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Lipper Other States Municipal Debt Funds Classification Average
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| Average Annual Return, Percent |
0.90%
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(0.12%)
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1.32%
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| S And P Municipal Bond Maryland Index [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
S&P Municipal Bond Maryland Index
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| Average Annual Return, Percent |
3.13%
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0.49%
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1.88%
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| Lipper Maryland Municipal Debt Funds Classification Average [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
Lipper Maryland Municipal Debt Funds Classification Average
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| Average Annual Return, Percent |
1.32%
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0.45%
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1.46%
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| S And P Municipal Bond Colorado Index [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
S&P Municipal Bond Colorado Index
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| Average Annual Return, Percent |
3.10%
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1.18%
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2.61%
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| S And P Municipal Bond Arizona Index [Member] |
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| Average Annual Return [Line Items] |
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| Line Graph and Table Measure Name |
S&P Municipal Bond Arizona Index
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| Average Annual Return, Percent |
2.71%
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0.89%
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2.15%
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