Investment Securities - Contractual Maturities of Available for Sale Debt Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Amortized Cost
Due in one year	$ 7,057
Due after one year through five years	30,645
Due after five years through ten years	94,221
Due after ten years	88,889
Residential mortgage-backed securities	895,279
Amortized Cost	1,116,091	$ 1,293,506
Fair Value
Due in one year	7,121
Due after one year through five years	31,222
Due after five years through ten years	96,722
Due after ten years	89,242
Residential mortgage-backed securities	904,502
Fair Value	$ 1,128,809	$ 1,339,473

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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