Fair Value of Assets and Liabilities - Carrying Amount and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Carrying Amount
Financial assets
Cash and cash equivalents	$ 401,995	$ 437,686
Debt securities, held-to-maturity	3,715,052	1,199,164
Loans receivable, net of ACL	15,064,529	13,259,366
Total financial assets	19,181,576	14,896,216
Financial liabilities
Term deposits	880,589	1,036,077
FHLB advances	1,800,000
Repurchase agreements and other borrowed funds	1,023,209	1,064,888
Subordinated debentures	132,782	132,620
Total financial liabilities	3,836,580	2,233,585
Estimated Fair Value | Level 1
Financial assets
Cash and cash equivalents	401,995	437,686
Debt securities, held-to-maturity	0	0
Loans receivable, net of ACL	0	0
Total financial assets	401,995	437,686
Financial liabilities
Term deposits	0	0
FHLB advances	0
Repurchase agreements and other borrowed funds	0	0
Subordinated debentures	0	0
Total financial liabilities	0	0
Estimated Fair Value | Level 2
Financial assets
Cash and cash equivalents	0	0
Debt securities, held-to-maturity	3,274,792	1,220,883
Loans receivable, net of ACL	0	0
Total financial assets	3,274,792	1,220,883
Financial liabilities
Term deposits	874,850	1,040,100
FHLB advances	1,799,936
Repurchase agreements and other borrowed funds	1,023,209	1,064,888
Subordinated debentures	122,549	131,513
Total financial liabilities	3,820,544	2,236,501
Estimated Fair Value | Level 3
Financial assets
Cash and cash equivalents	0	0
Debt securities, held-to-maturity	0	0
Loans receivable, net of ACL	14,806,354	13,422,898
Total financial assets	14,806,354	13,422,898
Financial liabilities
Term deposits	0	0
FHLB advances	0
Repurchase agreements and other borrowed funds	0	0
Subordinated debentures	0	0
Total financial liabilities	$ 0	$ 0