v3.26.1
Shareholder Report, Line Graph (Details) - USD ($)
 12 Months Ended 24 Months Ended 36 Months Ended 48 Months Ended 60 Months Ended 72 Months Ended 84 Months Ended 96 Months Ended 108 Months Ended 120 Months Ended
Mar. 01, 2016
Feb. 28, 2026
Feb. 28, 2017
Feb. 28, 2018
Feb. 28, 2019
Feb. 29, 2020
Feb. 28, 2021
Feb. 28, 2022
Feb. 28, 2023
Feb. 29, 2024
Feb. 28, 2025
Feb. 28, 2026
C000001519 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class I Shares at NAV                    
Accumulated Value $ 10,000   $ 10,061 $ 10,426 $ 10,731 $ 11,933 $ 11,933 $ 11,886 $ 10,977 $ 11,571 $ 11,990 $ 12,461
C000001516 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)                    
Accumulated Value 9,577   9,612 9,944 10,219 11,343 11,310 11,241 10,376 10,902 11,281 11,692
C000001524 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)                    
Accumulated Value 9,577   9,562 9,760 10,062 10,957 10,994 10,947 10,077 10,642 10,993 11,429
C000001527 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class I Shares at NAV                    
Accumulated Value 10,000   10,007 10,236 10,576 11,540 11,594 11,570 10,677 11,295 11,689 12,187
C000001531 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class I Shares at NAV                    
Accumulated Value 10,000   10,073 10,331 10,623 11,738 11,745 11,730 10,813 11,343 11,665 12,055
C000001528 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)                    
Accumulated Value 9,580   9,633 9,862 10,122 11,154 11,141 11,108 10,220 10,700 10,971 11,316
C000001536 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)                    
Accumulated Value 9,577   9,621 9,983 10,374 11,435 11,425 11,341 10,610 11,257 11,570 12,056
C000001539 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class I Shares at NAV                    
Accumulated Value 10,000   10,058 10,466 10,898 12,033 12,047 11,994 11,238 11,947 12,307 12,839
C000001543 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class I Shares at NAV                    
Accumulated Value 10,000   10,068 10,380 10,740 11,842 11,806 11,830 10,886 11,556 11,928 12,377
C000001540 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)                    
Accumulated Value 9,580   9,633 9,910 10,232 11,258 11,199 11,209 10,280 10,894 11,224 11,626
C000023361 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)                    
Accumulated Value 9,576   9,600 10,220 10,541 12,211 12,146 12,263 10,272 10,711 11,355 11,765
C000023364 [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Class I Shares at NAV                    
Accumulated Value 10,000   10,044 10,713 11,072 12,850 12,816 12,963 10,868 11,360 12,070 12,536
S And P Municipal Bond Index [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   S&P Municipal Bond Index                    
Accumulated Value 10,000   10,075 10,309 10,724 11,684 11,826 11,783 11,204 11,821 12,220 12,813
S And P Municipal Bond California Index [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   S&P Municipal Bond California Index                    
Accumulated Value 10,000   10,035 10,322 10,704 11,706 11,794 11,708 11,149 11,752 12,106 12,672
Lipper California Municipal Debt Funds Classification Average [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Lipper California Municipal Debt Funds Classification Average                    
Lipper Other States Municipal Debt Funds Classification Average [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Lipper Other States Municipal Debt Funds Classification Average                    
S And P Municipal Bond Connecticut Index [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   S&P Municipal Bond Connecticut Index                    
Accumulated Value 10,000   9,979 10,133 10,571 11,464 11,650 11,606 11,222 11,757 12,142 12,780
Lipper Massachusetts Municipal Debt Funds Classification Average [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Lipper Massachusetts Municipal Debt Funds Classification Average                    
S And P Municipal Bond Massachusetts Index [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   S&P Municipal Bond Massachusetts Index                    
Accumulated Value 10,000   9,994 10,203 10,586 11,508 11,606 11,506 10,952 11,500 11,831 12,426
S And P Municipal Bond New Jersey Index [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   S&P Municipal Bond New Jersey Index                    
Accumulated Value 10,000   10,129 10,588 11,086 12,227 12,388 12,350 11,892 12,590 13,009 13,684
Lipper New Jersey Municipal Debt Funds Classification Average [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Lipper New Jersey Municipal Debt Funds Classification Average                    
Lipper New York Municipal Debt Funds Classification Average [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   Lipper New York Municipal Debt Funds Classification Average                    
S And P Municipal Bond New York Index [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   S&P Municipal Bond New York Index                    
Accumulated Value 10,000   10,046 10,277 10,651 11,562 11,648 11,613 11,033 11,676 12,031 12,581
S And P Municipal Yield Index [Member]                        
Account Value [Line Items]                        
Line Graph and Table Measure Name   S&P Municipal Yield Index                    
Accumulated Value $ 10,000   $ 10,442 $ 10,859 $ 11,519 $ 13,115 $ 13,414 $ 13,658 $ 12,486 $ 13,571 $ 14,448 $ 14,986