v3.25.2
Shareholder Report, Average Annual Return (Details)
 12 Months Ended 60 Months Ended 120 Months Ended
Jul. 31, 2025
Jul. 31, 2025
Jul. 31, 2025
Columbia Minnesota Tax-Exempt Fund - Class A      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Class A (including sales charges)    
Average Annual Return, Percent (4.70%) (1.49%) 0.98%
Columbia Minnesota Tax-Exempt Fund - Class C      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Class C (including sales charges)    
Average Annual Return, Percent (3.39%) (1.64%) 0.54%
Columbia Minnesota Tax-Exempt Fund - Institutional Class      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Institutional Class    
Average Annual Return, Percent (1.46%) (0.67%) 1.54%
Columbia Minnesota Tax-Exempt Fund - Institutional 2 Class      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Institutional 2 Class    
Average Annual Return, Percent (1.46%) (0.65%) 1.53%
Columbia Minnesota Tax-Exempt Fund - Institutional 3 Class      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Institutional 3 Class    
Average Annual Return, Percent [1] (1.41%) (0.59%) 1.53%
Without Sales Load [Member] | Columbia Minnesota Tax-Exempt Fund - Class A      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Class A (excluding sales charges)    
Average Annual Return, Percent (1.75%) (0.91%) 1.29%
Without Sales Load [Member] | Columbia Minnesota Tax-Exempt Fund - Class C      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Class C (excluding sales charges)    
Average Annual Return, Percent (2.43%) (1.64%) 0.54%
Bloomberg Municipal Bond Index [Member]      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Bloomberg Municipal Bond Index    
Average Annual Return, Percent 0.00% 0.13% 2.11%
Bloomberg Minnesota Municipal Bond Index [Member]      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Bloomberg Minnesota Municipal Bond Index    
Average Annual Return, Percent 0.47% 0.00% 1.80%
[1] The returns shown for periods prior to March 1, 2017 (including Since Fund Inception returns, if shown) include the returns of Class A. These returns are adjusted to reflect any higher class-related operating expenses of the newer share classes, as applicable. Please visit columbiathreadneedleus.com/investment-products/mutual-funds/appended-performance for more information.