Investment Securities - Contractual Maturities of Debt Securities Available for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Amortized Cost
Due in one year	$ 11,305
Due after one year through five years	23,241
Due after five years through ten years	103,691
Due after ten years	88,305
Residential mortgage-backed securities	829,222
Amortized Cost	1,055,764	$ 1,116,091
Fair Value
Due in one year	11,303
Due after one year through five years	23,375
Due after five years through ten years	102,991
Due after ten years	81,811
Residential mortgage-backed securities	795,554
Total	$ 1,015,034	$ 1,128,809

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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