Fair Values of Assets and Liabilities - Schedule of Valuation Techniques and Significant Unobservable Inputs Used to Measure Both Recurring and Non Recurring (Details)	Mar. 31, 2025 USD ($) year $ / shares	Dec. 31, 2024 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	$ 4,220,305,000	$ 4,141,482,000	$ 4,387,598,000
Loans held-for-investment	126,521,000		144,365,000
MSRs	196,307,000	203,788,000	201,044,000	$ 192,456,000
Individually assessed loans - foreclosure probable and collateral-dependent	121,269,000		89,368,000
Municipal securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	188,149,000	184,593,000	140,590,000
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Individually assessed loans - foreclosure probable and collateral-dependent	121,300,000
Measured at fair value on a recurring basis:
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans held-for-sale	316,804,000	331,261,000	339,884,000
Loans held-for-investment	126,521,000	158,795,000	144,371,000
MSRs	196,307,000	203,788,000	201,044,000
Derivative assets	204,257,000	200,027,000	259,264,000
Measured at fair value on a recurring basis: | Municipal securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	188,149,000	184,593,000	140,590,000
Measured at fair value on a recurring basis: | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans held-for-sale	56,324,000	60,399,000	33,726,000
Loans held-for-investment	34,002,000	34,896,000	49,317,000
MSRs	196,307,000	203,788,000	201,044,000
Derivative assets	5,493,000	1,950,000	6,212,000
Measured at fair value on a recurring basis: | Level 3 | Municipal securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	$ 121,844,000	$ 121,607,000	$ 88,219,000
Measured at fair value on a recurring basis: | Discount rate | Level 3 | Discounted cash flows
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans held-for-sale, measurement input	0.0543
Measured at fair value on a recurring basis: | Discount rate | Level 3 | Discounted cash flows | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.0543
MSRs, measurement input	0.07
Measured at fair value on a recurring basis: | Discount rate | Level 3 | Discounted cash flows | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.0638
MSRs, measurement input	0.18
Measured at fair value on a recurring basis: | Discount rate | Level 3 | Discounted cash flows | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans held-for-sale, measurement input	0.0543
Loans held-for-investment, measurement input	0.0550
MSRs, measurement input	0.1094
Measured at fair value on a recurring basis: | Credit discount | Level 3 | Discounted cash flows | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans held-for-sale, measurement input	0
Loans held-for-investment, measurement input	0
Measured at fair value on a recurring basis: | Credit discount | Level 3 | Discounted cash flows | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans held-for-sale, measurement input	0.18
Loans held-for-investment, measurement input	0.10
Measured at fair value on a recurring basis: | Credit discount | Level 3 | Discounted cash flows | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans held-for-sale, measurement input	0.0071
Loans held-for-investment, measurement input	0.0112
Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) - current loans | Level 3 | Discounted cash flows
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.0892
Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) - current loans | Level 3 | Discounted cash flows | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
MSRs, measurement input	0.01
Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) - current loans | Level 3 | Discounted cash flows | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
MSRs, measurement input	0.91
Measured at fair value on a recurring basis: | Constant prepayment rate (CPR) - current loans | Level 3 | Discounted cash flows | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.0892
MSRs, measurement input	0.0892
Measured at fair value on a recurring basis: | Average life - delinquent loans (in years) | Level 3 | Discounted cash flows | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input | year	1.8
Measured at fair value on a recurring basis: | Average life - delinquent loans (in years) | Level 3 | Discounted cash flows | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input | year	11.2
Measured at fair value on a recurring basis: | Average life - delinquent loans (in years) | Level 3 | Discounted cash flows | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input | year	6.5
Measured at fair value on a recurring basis: | Cost of servicing | Level 3 | Discounted cash flows | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
MSRs, measurement input | $ / shares	70
Measured at fair value on a recurring basis: | Cost of servicing | Level 3 | Discounted cash flows | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
MSRs, measurement input | $ / shares	200
Measured at fair value on a recurring basis: | Cost of servicing | Level 3 | Discounted cash flows | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
MSRs, measurement input	76
Measured at fair value on a recurring basis: | Cost of servicing - delinquent | Level 3 | Discounted cash flows | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
MSRs, measurement input | $ / shares	200
Measured at fair value on a recurring basis: | Cost of servicing - delinquent | Level 3 | Discounted cash flows | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
MSRs, measurement input | $ / shares	1,000
Measured at fair value on a recurring basis: | Cost of servicing - delinquent | Level 3 | Discounted cash flows | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
MSRs, measurement input	402
Measured at fair value on a recurring basis: | Pull-through rate | Level 3 | Discounted cash flows | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivatives, measurement input	0.04
Measured at fair value on a recurring basis: | Pull-through rate | Level 3 | Discounted cash flows | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivatives, measurement input	1
Measured at fair value on a recurring basis: | Pull-through rate | Level 3 | Discounted cash flows | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivatives, measurement input	0.838
Measured at fair value on a non-recurring basis:
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Individually assessed loans - foreclosure probable and collateral-dependent	$ 121,269,000
Other real estate owned	22,625,000
Measured at fair value on a non-recurring basis: | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Individually assessed loans - foreclosure probable and collateral-dependent	121,269,000
Other real estate owned	$ 22,625,000
Measured at fair value on a non-recurring basis: | Appraisal adjustment - cost of sale | Level 3 | Appraisal value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans - collateral based, measurement input	0.10
Other real estate owned, measurement input	0.10
Measured at fair value on a non-recurring basis: | Appraisal adjustment - cost of sale | Level 3 | Appraisal value | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans - collateral based, measurement input	0.1000
Other real estate owned, measurement input	0.1000