Debt Securities Available-for-Sale - Comparative Summary Of Mortgage-Backed Securities And Other Securities Available-for-Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 1,019,607	$ 1,205,516
Gross unrealized gains	3	7,824
Gross unrealized losses	(67,437)	(5,103)
Estimated fair value	952,173	1,208,237
U.S. Government agency securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	76,150	2,344
Gross unrealized gains	0	0
Gross unrealized losses	(4,074)	(54)
Estimated fair value	72,076	2,290
US Government-Sponsored Enterprises Debt Securities, Pass Through Certificates
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	472,963	579,035
Gross unrealized gains	1	5,233
Gross unrealized losses	(40,346)	(2,862)
Estimated fair value	432,618	581,406
Government-Sponsored Enterprises Debt Securities, Real Estate Mortgage Investments Conduits
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	280,870	390,755
Gross unrealized gains	0	2,398
Gross unrealized losses	(16,146)	(1,443)
Estimated fair value	264,724	391,710
Real estate mortgage investment conduits (REMICs)
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	753,833	969,790
Gross unrealized gains	1	7,631
Gross unrealized losses	(56,492)	(4,305)
Estimated fair value	697,342	973,116
Municipal Bonds, Other Debt Obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	21	71
Gross unrealized gains	0	1
Gross unrealized losses	0	0
Estimated fair value	21	72
Corporate Bond Securities, Other Debt Obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	189,603	233,311
Gross unrealized gains	2	192
Gross unrealized losses	(6,871)	(744)
Estimated fair value	182,734	232,759
Other debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	189,624	233,382
Gross unrealized gains	2	193
Gross unrealized losses	(6,871)	(744)
Estimated fair value	$ 182,755	$ 232,831

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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