Securities Available for Sale - Amortized Cost and Estimated Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One	$ 2,307
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five	135,796
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10	131,656
Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 10	2,019,662
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	2,289,421	$ 2,685,648
Due within one year	0
Due after one year through five years	7,742
Due after five years through ten years	28,254
Due after ten years	235,070
Total	271,066
Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One	2,267
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five	126,723
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10	118,654
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10	1,724,485
Debt Securities, Available-for-Sale, Excluding Accrued Interest	1,972,129	2,666,275
Due within one year	0
Due after one year through five years	7,561
Due after five years through ten years	27,241
Due after ten years	223,605
Total	258,407
Collateralized mortgage obligations
Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	947,541	1,039,543
Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	793,699	1,026,430
Mortgage-backed securities: Residential
Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	544,084	769,113
Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	453,177	759,224
Mortgage-backed securities: Commercial
Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	417,241	595,659
Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	368,287	599,402
Asset-backed Securities
Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	153,539	153,564
Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	147,604	153,451
Municipal Bonds [Member]
Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	195,675	104,371
Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	182,752	105,284
US Treasury Notes Securities
Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	3,990	0
Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	$ 3,886	$ 0