| Component: (Network and Table) | |
|---|---|
| Network | 128 - Disclosure - Mortgage Servicing Rights (Tables) (http://www.bankmutualcorp.com/role/MortgageServicingRightsTables) |
| Table | Schedule of Finite-Lived Intangible Assets [Table] |
| Reporting Entity [Axis] | 0001123270 (http://www.sec.gov/CIK) |
| Finite-Lived Intangible Assets by Major Class [Axis] | Mortgage Servicing Rights [Member] |
| Finite-Lived Intangible Assets [Line Items] | Period [Axis] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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2016-01-01 - 2016-12-31 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Schedule Of Mortgage Servicing Rights [Table Text Block] | The activity in mortgage servicing rights during the years ended December 31 is presented in the following table.
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Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] | The following table shows the estimated future amortization expense for mortgage servicing rights for the years ended December 31:
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