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Debt Securities Available-for-Sale - Summary of Expected Maturity Distribution of Debt Securities Available-for-Sale, Other than Mortgage-Backed Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Amortized cost
Amortized cost	$ 1,130,384	$ 1,205,516
Estimated fair value
Estimated fair value	1,086,868	$ 1,208,237
Other Than Mortgage Backed Securities
Amortized cost
Due in one year or less	159,755
Due after one year through five years	113,115
Due after five years through ten years	1,572
Amortized cost	274,442
Estimated fair value
Due in one year or less	156,465
Due after one year through five years	107,719
Due after five years through ten years	1,445
Estimated fair value	$ 265,629

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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