0011 - Document - Document And Entity Information {Elements} link:calculationLink link:presentationLink link:definitionLink 010005 - Document - Risk/Return Summary {Unlabeled} (MFS Municipal Limited Maturity Fund (Prospectus Summary):) link:presentationLink link:calculationLink link:definitionLink 010010 - Schedule - Shareholder Fees link:presentationLink link:calculationLink link:definitionLink 010015 - Schedule - Annual Fund Operating Expenses link:presentationLink link:calculationLink link:definitionLink 010020 - Schedule - Expense Example {Transposed} link:presentationLink link:calculationLink link:definitionLink 010025 - Schedule - Expense Example, No Redemption {Transposed} link:presentationLink link:calculationLink link:definitionLink 010030 - Schedule - Annual Total Returns link:presentationLink link:calculationLink link:definitionLink 010035 - Schedule - Average Annual Total Returns {Transposed} link:presentationLink link:calculationLink link:definitionLink