Fair Value Measurements - Estimated fair value of company's financial instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Assets
Federal funds sold	$ 33,927	$ 20,391
Interest bearing deposits with other banks	265,272	1,680,945
Investment securities held-to-maturity	968,707	0
Bank owned life insurance	110,998	108,789
Liabilities
Interest bearing deposits	1,138,235	777,255
Customer repurchase agreements	35,100	23,918
Mortgage banking derivatives
Assets
Derivative asset	93	636
Carrying Value
Assets
Cash and due from banks	12,655	12,886
Federal funds sold	33,927	20,391
Interest bearing deposits with other banks	265,272	1,680,945
Investment securities available-for-sale, at fair value, net of allowance for credit loss of $0 in 2021	1,598,666	2,623,408
Investment securities held-to-maturity	1,093,374
Federal Reserve and Federal Home Loan Bank stock	65,067	34,153
Loans held for sale	6,734	47,218
Loans	7,635,632	7,065,598
Bank owned life insurance	110,998
Annuity investment	13,869
Liabilities
Noninterest bearing deposits	3,150,751	3,277,956
Interest bearing deposits	4,778,932	5,974,502
Time deposits	783,499	729,082
Customer repurchase agreements	35,100	23,918
Borrowings	1,044,795	369,670
Carrying Value | Mortgage banking derivatives
Assets
Derivative asset	93	636
Carrying Value | Interest Rate Caps
Assets
Derivative asset	31,039
Liabilities
Derivative liability	30,065	5,147
Carrying Value | Interest Rate Swap
Assets
Derivative asset		5,197
Carrying Value | Credit Risk Contract
Liabilities
Derivative liability	2	47
Fair Value
Assets
Cash and due from banks	12,655	12,886
Federal funds sold	33,927	20,391
Interest bearing deposits with other banks	265,272	1,680,945
Investment securities available-for-sale, at fair value, net of allowance for credit loss of $0 in 2021	1,598,666	2,623,408
Investment securities held-to-maturity	967,940
Loans held for sale	6,734	47,218
Loans	7,501,484	6,930,929
Bank owned life insurance	110,998
Annuity investment	13,869
Liabilities
Noninterest bearing deposits	3,150,751	3,277,956
Interest bearing deposits	4,778,932	5,974,502
Time deposits	790,418	736,001
Customer repurchase agreements	35,100	23,918
Borrowings	1,049,459	374,326
Fair Value | Mortgage banking derivatives
Assets
Derivative asset	93	636
Fair Value | Interest Rate Caps
Assets
Derivative asset	31,039
Liabilities
Derivative liability	30,065	5,147
Fair Value | Interest Rate Swap
Assets
Derivative asset		5,197
Fair Value | Credit Risk Contract
Liabilities
Derivative liability	2	47
Fair Value | Fair Value, Inputs, Level 1
Assets
Cash and due from banks	12,655	12,886
Federal funds sold	0	0
Interest bearing deposits with other banks	0	0
Investment securities available-for-sale, at fair value, net of allowance for credit loss of $0 in 2021	0	0
Investment securities held-to-maturity	0
Federal Reserve and Federal Home Loan Bank stock	0	0
Loans held for sale	0	0
Loans	0	0
Bank owned life insurance	0
Annuity investment	0
Liabilities
Noninterest bearing deposits	0	0
Interest bearing deposits	0	0
Time deposits	0	0
Customer repurchase agreements	0	0
Borrowings	0	0
Fair Value | Fair Value, Inputs, Level 1 | Mortgage banking derivatives
Assets
Derivative asset	0	0
Fair Value | Fair Value, Inputs, Level 1 | Interest Rate Caps
Assets
Derivative asset	0
Liabilities
Derivative liability	0	0
Fair Value | Fair Value, Inputs, Level 1 | Interest Rate Swap
Assets
Derivative asset		0
Fair Value | Fair Value, Inputs, Level 1 | Credit Risk Contract
Liabilities
Derivative liability	0	0
Fair Value | Fair Value, Inputs, Level 2
Assets
Cash and due from banks		0
Federal funds sold	33,927	20,391
Interest bearing deposits with other banks	265,272	1,680,945
Investment securities available-for-sale, at fair value, net of allowance for credit loss of $0 in 2021	1,598,666	2,611,408
Investment securities held-to-maturity	967,940
Federal Reserve and Federal Home Loan Bank stock	0	0
Loans held for sale	6,734	47,218
Loans		0
Bank owned life insurance	110,998
Annuity investment	13,869
Liabilities
Noninterest bearing deposits	3,150,751	3,277,956
Interest bearing deposits	4,778,932	5,974,502
Time deposits	790,418	736,001
Customer repurchase agreements	35,100	23,918
Borrowings	1,049,459	374,326
Fair Value | Fair Value, Inputs, Level 2 | Mortgage banking derivatives
Assets
Derivative asset		0
Fair Value | Fair Value, Inputs, Level 2 | Interest Rate Caps
Assets
Derivative asset	31,039
Liabilities
Derivative liability	30,065	5,147
Fair Value | Fair Value, Inputs, Level 2 | Interest Rate Swap
Assets
Derivative asset		5,197
Fair Value | Fair Value, Inputs, Level 2 | Credit Risk Contract
Liabilities
Derivative liability	2	47
Fair Value | Fair Value, Inputs, Level 3
Assets
Cash and due from banks	0	0
Federal funds sold	0	0
Interest bearing deposits with other banks	0	0
Investment securities available-for-sale, at fair value, net of allowance for credit loss of $0 in 2021	0	10,000
Investment securities held-to-maturity	0
Federal Reserve and Federal Home Loan Bank stock	0	0
Loans held for sale	0	0
Loans	7,501,484	6,930,929
Bank owned life insurance	0
Annuity investment	0
Liabilities
Noninterest bearing deposits	0	0
Interest bearing deposits	0	0
Time deposits	0	0
Customer repurchase agreements	0	0
Borrowings	0	0
Fair Value | Fair Value, Inputs, Level 3 | Mortgage banking derivatives
Assets
Derivative asset	93	636
Fair Value | Fair Value, Inputs, Level 3 | Interest Rate Caps
Assets
Derivative asset	0
Liabilities
Derivative liability	0	0
Fair Value | Fair Value, Inputs, Level 3 | Interest Rate Swap
Assets
Derivative asset		0
Fair Value | Fair Value, Inputs, Level 3 | Credit Risk Contract
Liabilities
Derivative liability	$ 0	$ 0