Fair Value of Assets and Liabilities - Significant Unobservable Inputs Used in Valuation of Level 3 Fair Value Measurements (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Mortgage Servicing Rights | Minimum | Level 3 | Third Party Valuations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Mortgage servicing rights	248.00%	242.00%
Mortgage Servicing Rights | Maximum | Level 3 | Third Party Valuations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Mortgage servicing rights	444.00%	441.00%
Mortgage Servicing Rights | Weighted Average | Level 3 | Third Party Valuations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Mortgage servicing rights	314.00%	384.00%
Collateral Dependent Loans | Minimum | Level 3 | Third Party Valuations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Collateral dependent loans	0.00%	0.00%
Collateral Dependent Loans | Maximum | Level 3 | Third Party Valuations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Collateral dependent loans	40.00%	40.00%
Collateral Dependent Loans | Weighted Average | Level 3 | Third Party Valuations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Collateral dependent loans	20.00%	20.00%
Foreclosed Assets Held-for-sale | Minimum | Level 3 | Third Party Valuations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Collateral dependent loans	0.00%	0.00%
Foreclosed Assets Held-for-sale | Maximum | Level 3 | Third Party Valuations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Collateral dependent loans	40.00%	40.00%
Foreclosed Assets Held-for-sale | Weighted Average | Level 3 | Third Party Valuations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Collateral dependent loans	35.00%	35.00%
Fair Value, Nonrecurring | Mortgage Servicing Rights
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value	$ 473	$ 517
Fair Value, Nonrecurring | Collateral Dependent Loans
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value	12,487	14,876
Fair Value, Nonrecurring | Collateral Dependent Loans | Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value	12,487	14,876
Fair Value, Nonrecurring | Foreclosed Assets Held-for-sale
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Assets, Fair Value	$ 3,303	$ 290