Fair Value Measurements (Details 6) - Non-recurring $ in Thousands	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Level 3
Valuation Methodology
Assets measured at fair value	$ 15,771	$ 18,130
Carrying Value | Level 3 | Collateral based measurements | Impaired loans
Valuation Methodology
Assets measured at fair value	9,171	11,991
Carrying Value | Level 3 | Discounted cash flows | Mortgage servicing rights
Valuation Methodology
Assets measured at fair value	4,017	3,804
Carrying Value | Level 3 | Appraisals trade publications and auction values | Repossessions
Valuation Methodology
Assets measured at fair value	2,214	1,976
Carrying Value | Level 3 | Appraisals | Other real estate
Valuation Methodology
Assets measured at fair value	369	359
Fair Value
Valuation Methodology
Assets measured at fair value	15,771	18,130
Fair Value | Level 3 | Collateral based measurements | Impaired loans
Valuation Methodology
Assets measured at fair value	9,171	11,991
Fair Value | Level 3 | Discounted cash flows | Mortgage servicing rights
Valuation Methodology
Assets measured at fair value	4,365	4,038
Fair Value | Level 3 | Appraisals trade publications and auction values | Repossessions
Valuation Methodology
Assets measured at fair value	2,368	2,144
Fair Value | Level 3 | Appraisals | Other real estate
Valuation Methodology
Assets measured at fair value	$ 374	$ 388
Discount for lack of marketability and current conditions | Level 3 | Collateral based measurements | Impaired loans | Minimum
Unobservable Inputs
Impaired loans unobservable inputs (as a percent)	0.10	0
Discount for lack of marketability and current conditions | Level 3 | Collateral based measurements | Impaired loans | Maximum
Unobservable Inputs
Impaired loans unobservable inputs (as a percent)	0.90	1
Discount for lack of marketability and current conditions | Level 3 | Collateral based measurements | Impaired loans | Weighted Average
Unobservable Inputs
Impaired loans unobservable inputs (as a percent)	0.300	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)	0.146	0.162
Constant prepayment rate (CPR) | Level 3 | Discounted cash flows | Mortgage servicing rights | Maximum
Unobservable Inputs
Mortgage servicing rights unobservable inputs (as a percent)	0.253	0.305
Constant prepayment rate (CPR) | Level 3 | Discounted cash flows | Mortgage servicing rights | Weighted Average
Unobservable Inputs
Mortgage servicing rights unobservable inputs (as a percent)	0.217	0.228
Discount rate | Level 3 | Discounted cash flows | Mortgage servicing rights | Minimum
Unobservable Inputs
Mortgage servicing rights unobservable inputs (as a percent)	0.088	0.083
Discount rate | Level 3 | Discounted cash flows | Mortgage servicing rights | Maximum
Unobservable Inputs
Mortgage servicing rights unobservable inputs (as a percent)	0.116	0.111
Discount rate | Level 3 | Discounted cash flows | Mortgage servicing rights | Weighted Average
Unobservable Inputs
Mortgage servicing rights unobservable inputs (as a percent)	0.089	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
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	0.16
Discount for lack of marketability | Level 3 | Appraisals trade publications and auction values | Repossessions | Weighted Average
Unobservable Inputs
Repossessions unobservable inputs (as a percent)	0.07	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	0.06
Discount for lack of marketability | Level 3 | Appraisals | Other real estate | Maximum
Unobservable Inputs
Other real estate unobservable inputs (as a percent)	0.13	0.13
Discount for lack of marketability | Level 3 | Appraisals | Other real estate | Weighted Average
Unobservable Inputs
Other real estate unobservable inputs (as a percent)	0.01	0.07