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Disclosures about Fair Value of Assets and Liabilities - Quantitative Information about Unobservable Inputs (Details) $ in Thousands	Mar. 31, 2024 USD ($)	Mar. 27, 2024 USD ($)	Dec. 31, 2023 USD ($)
Quantitative information about unobservable inputs
Servicing rights	$ 172,200		$ 158,457
Derivative assets		$ 0
Level 3 | Servicing rights | Loans funded through PPP, CARES Act
Quantitative information about unobservable inputs
Servicing rights	$ 4,988		$ 5,280
Level 3 | Servicing rights | Loans funded through PPP, CARES Act | Discount Rate
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.16		0.16
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		0.16
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		0.03
Level 3 | Servicing rights | Loans funded through PPP, CARES Act | Constant Prepayment Rate | Maximum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.14		0.14
Level 3 | Servicing rights | Loans funded through PPP, CARES Act | Constant Prepayment Rate | Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.09		0.09
Level 3 | Servicing rights | Single Family
Quantitative information about unobservable inputs
Servicing rights	$ 31,898		$ 30,959
Level 3 | Servicing rights | Single Family | Discount Rate | Minimum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.10		0.10
Level 3 | Servicing rights | Single Family | Discount Rate | Maximum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.11		0.11
Level 3 | Servicing rights | Single Family | Discount Rate | Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.10		0.10
Level 3 | Servicing rights | Single Family | Constant Prepayment Rate | Minimum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.06		0.06
Level 3 | Servicing rights | Single Family | Constant Prepayment Rate | Maximum
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.15		0.16
Level 3 | Servicing rights | Single Family | Constant Prepayment Rate | Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.07		0.07
Level 3 | Servicing rights | Multi-family
Quantitative information about unobservable inputs
Servicing rights	$ 135,314		$ 122,218
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	0.09		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	0.73		0.50
Level 3 | Servicing rights | Multi-family | Constant Prepayment Rate | Weighted average
Quantitative information about unobservable inputs
Servicing asset, measurement input	0.07		0.07
Level 3 | Collateral-dependent impaired loans
Quantitative information about unobservable inputs
Collateral-dependent loans	$ 420		$ 47,026
Level 3 | Collateral-dependent impaired loans | Minimum
Quantitative information about unobservable inputs
Marketability discount (as a percent)	0.24		0
Level 3 | Collateral-dependent impaired loans | Maximum
Quantitative information about unobservable inputs
Marketability discount (as a percent)	0.27		1
Level 3 | Collateral-dependent impaired loans | Weighted average
Quantitative information about unobservable inputs
Marketability discount (as a percent)	0.26		0.02
Level 3 | Available for sale securities | Measurement Input, Credit Spread
Quantitative information about unobservable inputs
Mortgage-backed - Non-agency residential- fair value option	$ 472,192		$ 485,500
Mortgage-backed - Non-agency residential- fair value option (as a percent)	0.02		0.02
Level 3 | Available for sale securities | Measurement Input, Credit Spread | Weighted average
Quantitative information about unobservable inputs
Mortgage-backed - Non-agency residential- fair value option (as a percent)	0.02		0.02
Level 3 | Interest rate lock commitments
Quantitative information about unobservable inputs
Derivative assets	$ 174		$ 140
Derivative liabilities	$ 22		$ 4
Level 3 | Interest rate lock commitments | Measurement Input, Maturity | Minimum
Quantitative information about unobservable inputs
Derivative assets, (as a percent)	0.50		0.45
Derivative liabilities (as a percent)	0.50		0.45
Level 3 | Interest rate lock commitments | Measurement Input, Maturity | Maximum
Quantitative information about unobservable inputs
Derivative assets, (as a percent)	0.99		0.99
Derivative liabilities (as a percent)	0.99		0.99
Level 3 | Interest rate lock commitments | Measurement Input, Maturity | Weighted average
Quantitative information about unobservable inputs
Derivative assets, (as a percent)	0.82		0.78
Derivative liabilities (as a percent)	0.82		0.78
Level 3 | Put Option | Measurement Input, Credit Spread
Quantitative information about unobservable inputs
Derivative assets	$ 22,976		$ 18,654
Derivative assets, (as a percent)	0.02		0.02
Level 3 | Put Option | Measurement Input, Credit Spread | Weighted average
Quantitative information about unobservable inputs
Derivative assets, (as a percent)	0.02		0.02
Level 3 | Interest Rate Floor | Discount Rate
Quantitative information about unobservable inputs
Derivative assets	$ 8,910		$ 6,576
Level 3 | Interest Rate Floor | Discount Rate | Minimum
Quantitative information about unobservable inputs
Derivative assets, (as a percent)	0.06		0.06
Level 3 | Interest Rate Floor | Discount Rate | Maximum
Quantitative information about unobservable inputs
Derivative assets, (as a percent)	0.08		0.07
Level 3 | Interest Rate Floor | Discount Rate | Weighted average
Quantitative information about unobservable inputs
Derivative assets, (as a percent)	0.07		0.07

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