v3.26.1
Shareholder Report, Average Annual Return (Details)
12 Months Ended 60 Months Ended 120 Months Ended
Feb. 28, 2026
Feb. 28, 2026
Feb. 28, 2026
Feb. 28, 2026
Feb. 28, 2026
C000001519 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class I Shares at NAV        
Average Annual Return, Percent 3.93% 0.87%     2.22%
C000001516 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at maximum sales charge (Offering Price)        
Average Annual Return, Percent (0.68%) (0.19%)     1.58%
C000001524 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at maximum sales charge (Offering Price)        
Average Annual Return, Percent (0.37%) (0.08%)     1.34%
C000001527 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class I Shares at NAV        
Average Annual Return, Percent 4.26% 1.00%     2.00%
C000001531 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class I Shares at NAV        
Average Annual Return, Percent 3.35% 0.52%     1.89%
C000001528 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at maximum sales charge (Offering Price)        
Average Annual Return, Percent (1.22%) (0.55%)     1.24%
C000001536 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at maximum sales charge (Offering Price)        
Average Annual Return, Percent (0.14%) 0.22%     1.89%
C000001539 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class I Shares at NAV        
Average Annual Return, Percent 4.33% 1.28%     2.53%
C000001543 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class I Shares at NAV        
Average Annual Return, Percent 3.77% 0.95%     2.16%
C000001540 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at maximum sales charge (Offering Price)        
Average Annual Return, Percent (0.78%) (0.11%)     1.52%
C000023361 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at maximum sales charge (Offering Price)        
Average Annual Return, Percent (0.70%) (1.49%)     1.64%
C000023364 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class I Shares at NAV        
Average Annual Return, Percent 3.86% (0.44%)     2.29%
Without Sales Load [Member] | C000137687 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class C Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 2.91% (0.14%) 1.37%    
Without Sales Load [Member] | C000001516 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 3.64% 0.67%   2.02%  
Without Sales Load [Member] | C000001524 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 3.96% 0.78% 1.78%    
Without Sales Load [Member] | C000137688 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class C Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 3.22% 0.00%   1.13%  
Without Sales Load [Member] | C000137689 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class C Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 2.39% (0.46%) 1.03%    
Without Sales Load [Member] | C000001528 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 3.14% 0.31%     1.68%
Without Sales Load [Member] | C000001536 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 4.20% 1.08%   2.33%  
Without Sales Load [Member] | C000137690 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class C Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 3.28% 0.25%     1.68%
Without Sales Load [Member] | C000137691 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class C Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 2.74% (0.06%) 1.30%    
Without Sales Load [Member] | C000001540 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 3.57% 0.75% 1.95%    
Without Sales Load [Member] | C000023361 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class A Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 3.62% (0.63%) 2.08%    
Without Sales Load [Member] | C000137692 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Class C Shares at NAV (excluding maximum sales charge)        
Average Annual Return, Percent 2.82% (1.42%) 1.43%    
S And P Municipal Bond Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P Municipal Bond Index        
Average Annual Return, Percent 4.85% 1.62%     2.51%
S And P Municipal Bond California Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P Municipal Bond California Index        
Average Annual Return, Percent 4.67% 1.45%     2.40%
Lipper California Municipal Debt Funds Classification Average [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Lipper California Municipal Debt Funds Classification Average        
Average Annual Return, Percent 3.84% 1.03% 2.13%    
Lipper Other States Municipal Debt Funds Classification Average [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Lipper Other States Municipal Debt Funds Classification Average        
Average Annual Return, Percent 4.26% 0.87% 1.69%    
S And P Municipal Bond Connecticut Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P Municipal Bond Connecticut Index        
Average Annual Return, Percent 5.26% 1.87%     2.48%
Lipper Massachusetts Municipal Debt Funds Classification Average [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Lipper Massachusetts Municipal Debt Funds Classification Average        
Average Annual Return, Percent 3.73% 0.58% 1.51%    
S And P Municipal Bond Massachusetts Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P Municipal Bond Massachusetts Index        
Average Annual Return, Percent 5.03% 1.37%     2.20%
S And P Municipal Bond New Jersey Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P Municipal Bond New Jersey Index        
Average Annual Return, Percent 5.19% 2.01%     3.19%
Lipper New Jersey Municipal Debt Funds Classification Average [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Lipper New Jersey Municipal Debt Funds Classification Average        
Average Annual Return, Percent 4.30% 1.26% 2.35%    
Lipper New York Municipal Debt Funds Classification Average [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Lipper New York Municipal Debt Funds Classification Average        
Average Annual Return, Percent 3.56% 1.02% 2.07%    
S And P Municipal Bond New York Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P Municipal Bond New York Index        
Average Annual Return, Percent 4.57% 1.55%     2.32%
S And P Municipal Yield Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P Municipal Yield Index        
Average Annual Return, Percent 3.73% 2.24%     4.13%