Disclosures about Fair Value of Assets and Liabilities - Quantitative Information about Unobservable Inputs (Details)	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Quantitative information about unobservable inputs
Servicing rights	$ 130,710,000	$ 110,348,000
Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input		12
Level 3 \| Servicing rights \| Loans funded through PPP, CARES Act
Quantitative information about unobservable inputs
Servicing rights	$ 4,019,000
Level 3 \| Servicing rights \| Loans funded through PPP, CARES Act \| Discount Rate
Quantitative information about unobservable inputs
Servicing rights		$ 2,769,000
Servicing asset, measurement input	0.16	16
Level 3 \| Servicing rights \| Loans funded through PPP, CARES Act \| Discount Rate \| Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.16	16
Level 3 \| Servicing rights \| Loans funded through PPP, CARES Act \| Constant Prepayment Rate \| Minimum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.03	10
Level 3 \| Servicing rights \| Loans funded through PPP, CARES Act \| Constant Prepayment Rate \| Maximum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.16	13
Level 3 \| Servicing rights \| Loans funded through PPP, CARES Act \| Constant Prepayment Rate \| Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.08
Level 3 \| Servicing rights \| Single Family
Quantitative information about unobservable inputs
Servicing rights	$ 29,632,000	$ 23,012,000
Level 3 \| Servicing rights \| Single Family \| Discount Rate \| Minimum
Quantitative information about unobservable inputs
Servicing asset, measurement input		9
Level 3 \| Servicing rights \| Single Family \| Discount Rate \| Maximum
Quantitative information about unobservable inputs
Servicing asset, measurement input		10
Level 3 \| Servicing rights \| Single Family \| Discount Rate \| Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input		9
Level 3 \| Servicing rights \| Single Family \| Constant Prepayment Rate \| Minimum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.07	0.10
Level 3 \| Servicing rights \| Single Family \| Constant Prepayment Rate \| Maximum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.09	0.13
Level 3 \| Servicing rights \| Single Family \| Constant Prepayment Rate \| Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input	7	0.11
Level 3 \| Servicing rights \| Single Family \| Mortgage Yield \| Minimum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.09
Level 3 \| Servicing rights \| Single Family \| Mortgage Yield \| Maximum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.10
Level 3 \| Servicing rights \| Single Family \| Mortgage Yield \| Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input	9
Level 3 \| Servicing rights \| Multi-family
Quantitative information about unobservable inputs
Servicing rights	$ 97,059,000	$ 84,567,000
Level 3 \| Servicing rights \| Multi-family \| Discount Rate \| Minimum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.08	0.08
Level 3 \| Servicing rights \| Multi-family \| Discount Rate \| Maximum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.13	0.13
Level 3 \| Servicing rights \| Multi-family \| Discount Rate \| Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.08	0.09
Level 3 \| Servicing rights \| Multi-family \| Constant Prepayment Rate \| Minimum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0	0
Level 3 \| Servicing rights \| Multi-family \| Constant Prepayment Rate \| Maximum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.50	0.50
Level 3 \| Servicing rights \| Multi-family \| Constant Prepayment Rate \| Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.03	0.04
Level 3 \| Collateral-dependent impaired loans
Quantitative information about unobservable inputs
Collateral-dependent impaired loans	$ 4,275,000	$ 4,263,000
Marketability discount (as a percent)	0.82
Level 3 \| Collateral-dependent impaired loans \| Minimum
Quantitative information about unobservable inputs
Marketability discount (as a percent)		0.44
Level 3 \| Collateral-dependent impaired loans \| Weighted average
Quantitative information about unobservable inputs
Marketability discount (as a percent)	0.82	0.73
Level 3 \| Interest Rate Lock Commitments
Quantitative information about unobservable inputs
Derivative assets	$ 299,000	$ 264,000
Derivative liabilities	$ 121,000	$ 41,000
Level 3 \| Interest Rate Lock Commitments \| Minimum
Quantitative information about unobservable inputs
Servicing asset, measurement input		63
Level 3 \| Interest Rate Lock Commitments \| Maximum
Quantitative information about unobservable inputs
Servicing asset, measurement input		99
Level 3 \| Interest Rate Lock Commitments \| Measurement Input, Maturity \| Minimum
Quantitative information about unobservable inputs
Loan closing rates (as a percent)	0.50	0.63
Loan closing rates (as a percent)	0.50
Level 3 \| Interest Rate Lock Commitments \| Measurement Input, Maturity \| Maximum
Quantitative information about unobservable inputs
Loan closing rates (as a percent)	0.99	0.99
Loan closing rates (as a percent)	0.99
Level 3 \| Interest Rate Lock Commitments \| Measurement Input, Maturity \| Weighted average
Quantitative information about unobservable inputs
Loan closing rates (as a percent)	81	0.83
Loan closing rates (as a percent)	81	83

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Value of input used to measure derivative asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Value of input used to measure derivative liability.

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No definition available.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Value of input used to measure servicing asset.

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