v3.26.1
Expense Example, No Redemption
Mar. 31, 2026
USD ($)
Eaton Vance National Limited Maturity Municipal Income Fund | Eaton Vance National Limited Maturity Municipal Income Fund | Class A  
Prospectus [Line Items]  
Expense Example, No Redemption, 1 Year $ 393
Expense Example, No Redemption, 3 Years 539
Expense Example, No Redemption, 5 Years 697
Expense Example, No Redemption, 10 Years 1,156
Eaton Vance National Limited Maturity Municipal Income Fund | Eaton Vance National Limited Maturity Municipal Income Fund | Class C  
Prospectus [Line Items]  
Expense Example, No Redemption, 1 Year 148
Expense Example, No Redemption, 3 Years 459
Expense Example, No Redemption, 5 Years 792
Expense Example, No Redemption, 10 Years 1,529
Eaton Vance National Limited Maturity Municipal Income Fund | Eaton Vance National Limited Maturity Municipal Income Fund | Class I  
Prospectus [Line Items]  
Expense Example, No Redemption, 1 Year 55
Expense Example, No Redemption, 3 Years 173
Expense Example, No Redemption, 5 Years 302
Expense Example, No Redemption, 10 Years 677
Eaton Vance Short Duration Municipal Opportunities Fund | Eaton Vance Short Duration Municipal Opportunities Fund | Class A  
Prospectus [Line Items]  
Expense Example, No Redemption, 1 Year 390
Expense Example, No Redemption, 3 Years 529
Expense Example, No Redemption, 5 Years 681
Expense Example, No Redemption, 10 Years 1,121
Eaton Vance Short Duration Municipal Opportunities Fund | Eaton Vance Short Duration Municipal Opportunities Fund | Class C  
Prospectus [Line Items]  
Expense Example, No Redemption, 1 Year 144
Expense Example, No Redemption, 3 Years 446
Expense Example, No Redemption, 5 Years 771
Expense Example, No Redemption, 10 Years 1,486
Eaton Vance Short Duration Municipal Opportunities Fund | Eaton Vance Short Duration Municipal Opportunities Fund | Class I  
Prospectus [Line Items]  
Expense Example, No Redemption, 1 Year 52
Expense Example, No Redemption, 3 Years 164
Expense Example, No Redemption, 5 Years 285
Expense Example, No Redemption, 10 Years $ 640