Shareholder Report, Holdings (Details)	Aug. 31, 2026
C000005543 \| Maryland
Holdings [Line Items]
Percent of Net Asset Value	93.50%
C000005543 \| Puerto Rico
Holdings [Line Items]
Percent of Net Asset Value	4.80%
C000005543 \| Alabama
Holdings [Line Items]
Percent of Net Asset Value	1.10%
C000005543 \| California
Holdings [Line Items]
Percent of Net Asset Value	0.60%
C000005543 \| Texas
Holdings [Line Items]
Percent of Net Asset Value	0.30%
C000005543 \| Investment TypeOther Holdings Grouping
Holdings [Line Items]
Percent of Net Asset Value	(0.30%)
C000005543 \| Genl Obligations - Local
Holdings [Line Items]
Percent of Net Asset Value	22.80%
C000005543 \| Housing Finance Revenue
Holdings [Line Items]
Percent of Net Asset Value	16.00%
C000005543 \| Dedicated Tax Revenue
Holdings [Line Items]
Percent of Net Asset Value	14.70%
C000005543 \| General Obligations - State
Holdings [Line Items]
Percent of Net Asset Value	12.60%
C000005543 \| Hospital Revenue
Holdings [Line Items]
Percent of Net Asset Value	12.30%
C000005543 \| Air & Sea Transportation
Holdings [Line Items]
Percent of Net Asset Value	10.70%
C000005543 \| Lease Revenue
Holdings [Line Items]
Percent of Net Asset Value	2.30%
C000005543 \| Industrial & Pollution Control Revenue
Holdings [Line Items]
Percent of Net Asset Value	2.20%
C000005543 \| Water & Sewer Revenue
Holdings [Line Items]
Percent of Net Asset Value	1.80%
C000005543 \| Other 2
Holdings [Line Items]
Percent of Net Asset Value	4.60%
C000193182 \| Maryland
Holdings [Line Items]
Percent of Net Asset Value	93.50%
C000193182 \| Puerto Rico
Holdings [Line Items]
Percent of Net Asset Value	4.80%
C000193182 \| Alabama
Holdings [Line Items]
Percent of Net Asset Value	1.10%
C000193182 \| California
Holdings [Line Items]
Percent of Net Asset Value	0.60%
C000193182 \| Texas
Holdings [Line Items]
Percent of Net Asset Value	0.30%
C000193182 \| Investment TypeOther Holdings Grouping
Holdings [Line Items]
Percent of Net Asset Value	(0.30%)
C000193182 \| Genl Obligations - Local
Holdings [Line Items]
Percent of Net Asset Value	22.80%
C000193182 \| Housing Finance Revenue
Holdings [Line Items]
Percent of Net Asset Value	16.00%
C000193182 \| Dedicated Tax Revenue
Holdings [Line Items]
Percent of Net Asset Value	14.70%
C000193182 \| General Obligations - State
Holdings [Line Items]
Percent of Net Asset Value	12.60%
C000193182 \| Hospital Revenue
Holdings [Line Items]
Percent of Net Asset Value	12.30%
C000193182 \| Air & Sea Transportation
Holdings [Line Items]
Percent of Net Asset Value	10.70%
C000193182 \| Lease Revenue
Holdings [Line Items]
Percent of Net Asset Value	2.30%
C000193182 \| Industrial & Pollution Control Revenue
Holdings [Line Items]
Percent of Net Asset Value	2.20%
C000193182 \| Water & Sewer Revenue
Holdings [Line Items]
Percent of Net Asset Value	1.80%
C000193182 \| Other 2
Holdings [Line Items]
Percent of Net Asset Value	4.60%