v3.26.3
Shareholder Report, Average Annual Return (Details)
 12 Months Ended 60 Months Ended 120 Months Ended
Aug. 31, 2026
Aug. 31, 2026
Aug. 31, 2026
C000135926 [Member]      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Nomura Tax‑Free California Fund (Institutional Class) – including sales charge    
Average Annual Return, Percent 5.61% 0.29% 2.04%
C000006417 [Member]      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Nomura Tax‑Free California Fund (Class C) – including sales charge    
Average Annual Return, Percent 3.56% (0.70%) 1.03%
C000006415 [Member]      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Nomura Tax‑Free California Fund (Class A) – including sales charge    
Average Annual Return, Percent 0.64% (0.88%) 1.33%
Without Sales Load [Member] | C000135926 [Member]      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Nomura Tax‑Free California Fund (Institutional Class) – excluding sales charge    
Average Annual Return, Percent 5.61% 0.29% 2.04%
Without Sales Load [Member] | C000006417 [Member]      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Nomura Tax‑Free California Fund (Class C) – excluding sales charge    
Average Annual Return, Percent 4.56% (0.70%) 1.03%
Without Sales Load [Member] | C000006415 [Member]      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Nomura Tax‑Free California Fund (Class A) – excluding sales charge    
Average Annual Return, Percent 5.35% 0.04% 1.79%
Bloomberg Municipal Bond Index [Member]      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Bloomberg Municipal Bond Index    
Average Annual Return, Percent 4.12% 0.54% 1.91%