Fair Value of Financial Instruments - Hierarchy Table on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Financial assets
Investment securities available-for-sale, at fair value	$ 3,222,095	$ 4,273,864
Derivative assets	44,880	11,989
Financial liabilities
Interest rate swaps	4,241	5,263
U.S. Treasury
Financial assets
Investment securities available-for-sale, at fair value	13,990	57,866
Agency
Financial assets
Investment securities available-for-sale, at fair value	375,777	432,135
Corporate debt
Financial assets
Investment securities available-for-sale, at fair value	595,065	453,861
Municipal bonds
Financial assets
Investment securities available-for-sale, at fair value	415,284	1,089,913
Collateralized mortgage obligations
Financial assets
Investment securities available-for-sale, at fair value	855,256	676,643
Mortgage-backed securities
Financial assets
Investment securities available-for-sale, at fair value	966,723	1,563,446
Level 1
Financial assets
Investment securities available-for-sale, at fair value	0	0
Derivative assets	0	0
Financial liabilities
Interest rate swaps	0	0
Level 2
Financial assets
Investment securities available-for-sale, at fair value	3,222,095	4,273,864
Derivative assets	42,972	10,100
Financial liabilities
Interest rate swaps	4,241	5,263
Level 3
Financial assets
Investment securities available-for-sale, at fair value	0	0
Derivative assets	1,908	1,889
Financial liabilities
Interest rate swaps	0	0
Recurring
Financial assets
Investment securities available-for-sale, at fair value	3,222,095	4,273,864
Derivative assets	44,880	11,989
Recurring | Interest rate swaps contracts
Financial assets
Derivative assets	42,972	10,100
Financial liabilities
Interest rate swaps	4,241	5,263
Recurring | Equity warrants
Financial assets
Derivative assets	1,908	1,889
Recurring | U.S. Treasury
Financial assets
Investment securities available-for-sale, at fair value	13,990	57,866
Recurring | Agency
Financial assets
Investment securities available-for-sale, at fair value	375,777	432,135
Recurring | Corporate debt
Financial assets
Investment securities available-for-sale, at fair value	595,065	453,861
Recurring | Municipal bonds
Financial assets
Investment securities available-for-sale, at fair value	415,284	1,089,913
Recurring | Collateralized mortgage obligations
Financial assets
Investment securities available-for-sale, at fair value	855,256	676,643
Recurring | Mortgage-backed securities
Financial assets
Investment securities available-for-sale, at fair value	966,723	1,563,446
Recurring | Level 1
Financial assets
Investment securities available-for-sale, at fair value	0	0
Derivative assets	0	0
Recurring | Level 1 | Interest rate swaps contracts
Financial assets
Derivative assets	0	0
Financial liabilities
Interest rate swaps	0	0
Recurring | Level 1 | Equity warrants
Financial assets
Derivative assets	0	0
Recurring | Level 1 | U.S. Treasury
Financial assets
Investment securities available-for-sale, at fair value	0	0
Recurring | Level 1 | Agency
Financial assets
Investment securities available-for-sale, at fair value	0	0
Recurring | Level 1 | Corporate debt
Financial assets
Investment securities available-for-sale, at fair value	0	0
Recurring | Level 1 | Municipal bonds
Financial assets
Investment securities available-for-sale, at fair value	0	0
Recurring | Level 1 | Collateralized mortgage obligations
Financial assets
Investment securities available-for-sale, at fair value	0	0
Recurring | Level 1 | Mortgage-backed securities
Financial assets
Investment securities available-for-sale, at fair value	0	0
Recurring | Level 2
Financial assets
Investment securities available-for-sale, at fair value	3,222,095	4,273,864
Derivative assets	42,972	10,100
Recurring | Level 2 | Interest rate swaps contracts
Financial assets
Derivative assets	42,972	10,100
Financial liabilities
Interest rate swaps	4,241	5,263
Recurring | Level 2 | Equity warrants
Financial assets
Derivative assets	0	0
Recurring | Level 2 | U.S. Treasury
Financial assets
Investment securities available-for-sale, at fair value	13,990	57,866
Recurring | Level 2 | Agency
Financial assets
Investment securities available-for-sale, at fair value	375,777	432,135
Recurring | Level 2 | Corporate debt
Financial assets
Investment securities available-for-sale, at fair value	595,065	453,861
Recurring | Level 2 | Municipal bonds
Financial assets
Investment securities available-for-sale, at fair value	415,284	1,089,913
Recurring | Level 2 | Collateralized mortgage obligations
Financial assets
Investment securities available-for-sale, at fair value	855,256	676,643
Recurring | Level 2 | Mortgage-backed securities
Financial assets
Investment securities available-for-sale, at fair value	966,723	1,563,446
Recurring | Level 3
Financial assets
Investment securities available-for-sale, at fair value	0	0
Derivative assets	1,908	1,889
Recurring | Level 3 | Interest rate swaps contracts
Financial assets
Derivative assets	0	0
Financial liabilities
Interest rate swaps	0	0
Recurring | Level 3 | Equity warrants
Financial assets
Derivative assets	1,908	1,889
Recurring | Level 3 | U.S. Treasury
Financial assets
Investment securities available-for-sale, at fair value	0	0
Recurring | Level 3 | Agency
Financial assets
Investment securities available-for-sale, at fair value	0	0
Recurring | Level 3 | Corporate debt
Financial assets
Investment securities available-for-sale, at fair value	0	0
Recurring | Level 3 | Municipal bonds
Financial assets
Investment securities available-for-sale, at fair value	0	0
Recurring | Level 3 | Collateralized mortgage obligations
Financial assets
Investment securities available-for-sale, at fair value	0	0
Recurring | Level 3 | Mortgage-backed securities
Financial assets
Investment securities available-for-sale, at fair value	$ 0	$ 0