Investment Securities - Contractual Maturities of Debt Securities Held to Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Amortized Cost
Due in one year	$ 39,603
Due after one year through five years	215,490
Due after five years through ten years	46,097
Due after ten years	177,720
Residential mortgage-backed securities	2,594,295
Amortized Cost	3,073,205	$ 2,668,697
Fair Value
Due in one year	39,663
Due after one year through five years	217,668
Due after five years through ten years	45,919
Due after ten years	170,103
Residential mortgage-backed securities	2,440,498
Total	$ 2,913,851	$ 2,660,605

Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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