Fair Value of Assets and Liabilities - Fair Value Measurements on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Financial Assets
Debt securities, available-for-sale	$ 5,755,076	$ 9,170,849
Recurring Measurements
Financial Assets
Loans held for sale, at fair value	21,720	60,797
Total assets measured at fair value on a recurring basis	5,786,290	9,235,588
Total financial liabilities		80
Interest rate caps \| Recurring Measurements
Financial Assets
Interest rate caps	7,643	934
Interest rate locks \| Recurring Measurements
Financial Assets
Interest rate caps	99	3,008
TBA hedge \| Recurring Measurements
Financial Assets
Interest rate caps	1,752
TBA hedge		80
U.S. government and federal agency \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	443,466	1,346,749
U.S. government sponsored enterprises \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	288,532	240,693
State and local governments \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	411,855	488,858
Corporate bonds \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	83,731	180,752
Residential mortgage-backed securities \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	3,387,378	5,699,659
Commercial mortgage-backed securities \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	1,140,114	1,214,138
Level 1 \| Recurring Measurements
Financial Assets
Loans held for sale, at fair value	0	0
Total assets measured at fair value on a recurring basis	0	0
Total financial liabilities		0
Level 1 \| Interest rate caps \| Recurring Measurements
Financial Assets
Interest rate caps	0	0
Level 1 \| Interest rate locks \| Recurring Measurements
Financial Assets
Interest rate caps	0	0
Level 1 \| TBA hedge \| Recurring Measurements
Financial Assets
Interest rate caps	0
TBA hedge		0
Level 1 \| U.S. government and federal agency \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 1 \| U.S. government sponsored enterprises \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 1 \| State and local governments \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 1 \| Corporate bonds \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 1 \| Residential mortgage-backed securities \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 1 \| Commercial mortgage-backed securities \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 2 \| Recurring Measurements
Financial Assets
Loans held for sale, at fair value	21,720	60,797
Total assets measured at fair value on a recurring basis	5,786,290	9,235,588
Total financial liabilities		80
Level 2 \| Interest rate caps \| Recurring Measurements
Financial Assets
Interest rate caps	7,643	934
Level 2 \| Interest rate locks \| Recurring Measurements
Financial Assets
Interest rate caps	99	3,008
Level 2 \| TBA hedge \| Recurring Measurements
Financial Assets
Interest rate caps	1,752
TBA hedge		80
Level 2 \| U.S. government and federal agency \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	443,466	1,346,749
Level 2 \| U.S. government sponsored enterprises \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	288,532	240,693
Level 2 \| State and local governments \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	411,855	488,858
Level 2 \| Corporate bonds \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	83,731	180,752
Level 2 \| Residential mortgage-backed securities \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	3,387,378	5,699,659
Level 2 \| Commercial mortgage-backed securities \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	1,140,114	1,214,138
Level 3 \| Recurring Measurements
Financial Assets
Loans held for sale, at fair value	0	0
Total assets measured at fair value on a recurring basis	0	0
Total financial liabilities		0
Level 3 \| Interest rate caps \| Recurring Measurements
Financial Assets
Interest rate caps	0	0
Level 3 \| Interest rate locks \| Recurring Measurements
Financial Assets
Interest rate caps	0	0
Level 3 \| TBA hedge \| Recurring Measurements
Financial Assets
Interest rate caps	0
TBA hedge		0
Level 3 \| U.S. government and federal agency \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 3 \| U.S. government sponsored enterprises \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 3 \| State and local governments \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 3 \| Corporate bonds \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 3 \| Residential mortgage-backed securities \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	0	0
Level 3 \| Commercial mortgage-backed securities \| Recurring Measurements
Financial Assets
Debt securities, available-for-sale	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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