Fair Values of Assets and Liabilities - Schedule of Valuation Techniques and Significant Unobservable Inputs Used to Measure Both Recurring and Non Recurring (Details)	Dec. 31, 2023 USD ($) year $ / shares	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	$ 3,502,915,000	$ 3,243,017,000
Loans held-for-investment	155,261,000	179,932,000
MSRs	192,456,000	230,225,000	$ 147,571,000	$ 92,081,000
Individually assessed loans - foreclosure probable and collateral-dependent	91,153,000	90,197,000
Municipal securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	140,958,000	168,655,000
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Individually assessed loans - foreclosure probable and collateral-dependent	91,200,000
Measured at fair value on a recurring basis:
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans held-for-sale	292,722,000	299,935,000
Loans held-for-investment	155,261,000	179,932,000
MSRs	192,456,000	230,225,000
Derivative assets	275,726,000	296,848,000
Measured at fair value on a recurring basis: | Municipal securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	140,958,000	168,655,000
Measured at fair value on a recurring basis: | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage loans held-for-sale	26,835,000	48,655,000
Loans held-for-investment	60,670,000	84,165,000
MSRs	192,456,000	230,225,000
Derivative assets	4,510,000	1,711,000
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	$ 86,237,000	$ 117,537,000
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	0.0611
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	0.0611
MSRs, measurement input	0.06
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	0.0700
MSRs, measurement input	0.25
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	0.0611
Loans held-for-investment, measurement input	0.0618
MSRs, measurement input	0.1100
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	0.11
Loans held-for-investment, measurement input	0.29
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	0.0040
Loans held-for-investment, measurement input	0.0096
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	0.0791
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
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	0.90
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	0.0791
MSRs, measurement input	0.0791
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	1.1
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	10.6
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
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	77
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	393
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	0.06
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	0.7396
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	$ 91,153,000
Other real estate owned	13,309,000
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	91,153,000
Other real estate owned	$ 13,309,000
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