Fair Value Measurements (Details 6) - Non-recurring $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Level 3
Valuation Methodology
Assets measured at fair value	$ 18,130	$ 21,837
Carrying Value | Level 3 | Collateral based measurements | Collateral-dependent impaired loans
Valuation Methodology
Assets measured at fair value	11,991	8,492
Carrying Value | Level 3 | Discounted cash flows | Mortgage servicing rights
Valuation Methodology
Assets measured at fair value	3,804	4,200
Carrying Value | Level 3 | Appraisals trade publications and auction values | Repossessions
Valuation Methodology
Assets measured at fair value	1,976	8,623
Carrying Value | Level 3 | Appraisals | Other real estate
Valuation Methodology
Assets measured at fair value	359	522
Fair Value
Valuation Methodology
Assets measured at fair value	18,130	21,837
Fair Value | Level 3 | Collateral based measurements | Collateral-dependent impaired loans
Valuation Methodology
Assets measured at fair value	11,991	8,492
Fair Value | Level 3 | Discounted cash flows | Mortgage servicing rights
Valuation Methodology
Assets measured at fair value	4,038	5,986
Fair Value | Level 3 | Appraisals trade publications and auction values | Repossessions
Valuation Methodology
Assets measured at fair value	2,144	9,211
Fair Value | Level 3 | Appraisals | Other real estate
Valuation Methodology
Assets measured at fair value	$ 388	$ 564
Discount for lack of marketability and current conditions | Level 3 | Collateral based measurements | Collateral-dependent impaired loans | Minimum
Unobservable Inputs
Impaired loans unobservable inputs (as a percent)	0	0
Discount for lack of marketability and current conditions | Level 3 | Collateral based measurements | Collateral-dependent impaired loans | Maximum
Unobservable Inputs
Impaired loans unobservable inputs (as a percent)	1	0.90
Discount for lack of marketability and current conditions | Level 3 | Collateral based measurements | Collateral-dependent impaired loans | Weighted Average [Member]
Unobservable Inputs
Impaired loans unobservable inputs (as a percent)	0.437
Constant prepayment rate (CPR) | Level 3 | Discounted cash flows | Mortgage servicing rights | Minimum
Unobservable Inputs
Mortgage servicing rights unobservable inputs (as a percent)	0.162	0.102
Constant prepayment rate (CPR) | Level 3 | Discounted cash flows | Mortgage servicing rights | Maximum
Unobservable Inputs
Mortgage servicing rights unobservable inputs (as a percent)	0.305	0.281
Constant prepayment rate (CPR) | Level 3 | Discounted cash flows | Mortgage servicing rights | Weighted Average [Member]
Unobservable Inputs
Mortgage servicing rights unobservable inputs (as a percent)	0.228
Discount rate | Level 3 | Discounted cash flows | Mortgage servicing rights | Minimum
Unobservable Inputs
Mortgage servicing rights unobservable inputs (as a percent)	0.083	0.093
Discount rate | Level 3 | Discounted cash flows | Mortgage servicing rights | Maximum
Unobservable Inputs
Mortgage servicing rights unobservable inputs (as a percent)	0.111	0.121
Discount rate | Level 3 | Discounted cash flows | Mortgage servicing rights | Weighted Average [Member]
Unobservable Inputs
Mortgage servicing rights unobservable inputs (as a percent)	0.085
Discount for lack of marketability | Level 3 | Appraisals trade publications and auction values | Repossessions | Minimum
Unobservable Inputs
Repossessions unobservable inputs (as a percent)	0	0.03
Discount for lack of marketability | Level 3 | Appraisals trade publications and auction values | Repossessions | Maximum
Unobservable Inputs
Repossessions unobservable inputs (as a percent)	0.16	0.25
Discount for lack of marketability | Level 3 | Appraisals trade publications and auction values | Repossessions | Weighted Average [Member]
Unobservable Inputs
Repossessions unobservable inputs (as a percent)	0.08
Discount for lack of marketability | Level 3 | Appraisals | Other real estate | Minimum
Unobservable Inputs
Other real estate unobservable inputs (as a percent)	0.06	0
Discount for lack of marketability | Level 3 | Appraisals | Other real estate | Maximum
Unobservable Inputs
Other real estate unobservable inputs (as a percent)	0.13	0.11
Discount for lack of marketability | Level 3 | Appraisals | Other real estate | Weighted Average [Member]
Unobservable Inputs
Other real estate unobservable inputs (as a percent)	0.07