Debt Securities Available for Sale - Expected Maturities of Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Amortized Cost
One year or less	$ 915
More than one year to five years	56,479
More than five years to ten years	105,603
Available-for-sale debt securities, allocated and single maturity date, total	162,997
Mortgage-backed securities and collateralized mortgage obligations	1,452,210
Amortized Cost	1,615,207	$ 1,701,379
Fair Value
One year or less	914
More than one year to five years	54,788
More than five years to ten years	99,593
Available-for-sale debt securities, allocated and single maturity date, total	155,295
Mortgage-backed securities and collateralized mortgage obligations	1,335,347
Fair Value	$ 1,490,642	$ 1,703,847

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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