v3.26.3
Shareholder Report, Holdings (Details)
Aug. 31, 2026
C000005562 | Texas  
Holdings [Line Items]  
Percent of Net Asset Value 12.40%
C000005562 | New York  
Holdings [Line Items]  
Percent of Net Asset Value 10.50%
C000005562 | Alabama  
Holdings [Line Items]  
Percent of Net Asset Value 8.10%
C000005562 | Puerto Rico  
Holdings [Line Items]  
Percent of Net Asset Value 6.00%
C000005562 | Virginia  
Holdings [Line Items]  
Percent of Net Asset Value 5.10%
C000005562 | Colorado  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
C000005562 | Illinois  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
C000005562 | California  
Holdings [Line Items]  
Percent of Net Asset Value 3.90%
C000005562 | Florida  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
C000005562 | Investment TypeOther Holdings Grouping  
Holdings [Line Items]  
Percent of Net Asset Value 41.30%
C000005562 | Hospital Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 19.90%
C000005562 | Air & Sea Transportation  
Holdings [Line Items]  
Percent of Net Asset Value 16.80%
C000005562 | Housing Finance Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 14.70%
C000005562 | General Obligations - State  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
C000005562 | Educational Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 5.80%
C000005562 | Dedicated Tax Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
C000005562 | Industrial & Pollution Control Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
C000005562 | Genl Obligations - Local  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
C000005562 | Electric Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
C000005562 | Other 2  
Holdings [Line Items]  
Percent of Net Asset Value 16.70%
C000117196 | Texas  
Holdings [Line Items]  
Percent of Net Asset Value 12.40%
C000117196 | New York  
Holdings [Line Items]  
Percent of Net Asset Value 10.50%
C000117196 | Alabama  
Holdings [Line Items]  
Percent of Net Asset Value 8.10%
C000117196 | Puerto Rico  
Holdings [Line Items]  
Percent of Net Asset Value 6.00%
C000117196 | Virginia  
Holdings [Line Items]  
Percent of Net Asset Value 5.10%
C000117196 | Colorado  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
C000117196 | Illinois  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
C000117196 | California  
Holdings [Line Items]  
Percent of Net Asset Value 3.90%
C000117196 | Florida  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
C000117196 | Investment TypeOther Holdings Grouping  
Holdings [Line Items]  
Percent of Net Asset Value 41.30%
C000117196 | Hospital Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 19.90%
C000117196 | Air & Sea Transportation  
Holdings [Line Items]  
Percent of Net Asset Value 16.80%
C000117196 | Housing Finance Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 14.70%
C000117196 | General Obligations - State  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
C000117196 | Educational Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 5.80%
C000117196 | Dedicated Tax Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
C000117196 | Industrial & Pollution Control Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
C000117196 | Genl Obligations - Local  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
C000117196 | Electric Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
C000117196 | Other 2  
Holdings [Line Items]  
Percent of Net Asset Value 16.70%
C000177206 | Texas  
Holdings [Line Items]  
Percent of Net Asset Value 12.40%
C000177206 | New York  
Holdings [Line Items]  
Percent of Net Asset Value 10.50%
C000177206 | Alabama  
Holdings [Line Items]  
Percent of Net Asset Value 8.10%
C000177206 | Puerto Rico  
Holdings [Line Items]  
Percent of Net Asset Value 6.00%
C000177206 | Virginia  
Holdings [Line Items]  
Percent of Net Asset Value 5.10%
C000177206 | Colorado  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
C000177206 | Illinois  
Holdings [Line Items]  
Percent of Net Asset Value 4.50%
C000177206 | California  
Holdings [Line Items]  
Percent of Net Asset Value 3.90%
C000177206 | Florida  
Holdings [Line Items]  
Percent of Net Asset Value 3.20%
C000177206 | Investment TypeOther Holdings Grouping  
Holdings [Line Items]  
Percent of Net Asset Value 41.30%
C000177206 | Hospital Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 19.90%
C000177206 | Air & Sea Transportation  
Holdings [Line Items]  
Percent of Net Asset Value 16.80%
C000177206 | Housing Finance Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 14.70%
C000177206 | General Obligations - State  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
C000177206 | Educational Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 5.80%
C000177206 | Dedicated Tax Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
C000177206 | Industrial & Pollution Control Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
C000177206 | Genl Obligations - Local  
Holdings [Line Items]  
Percent of Net Asset Value 4.90%
C000177206 | Electric Revenue  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
C000177206 | Other 2  
Holdings [Line Items]  
Percent of Net Asset Value 16.70%