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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	Dec. 31, 2021	Dec. 31, 2020
Amortized cost
Amortized cost	$ 1,205,516	$ 1,246,673
Estimated fair value
Estimated fair value	1,208,237	$ 1,264,805
Other Than Mortgage Backed Securities
Amortized cost
Due in one year or less	57,299
Due after one year through five years	161,074
Due after five years through ten years	17,353
Amortized cost	235,726
Estimated fair value
Due in one year or less	57,295
Due after one year through five years	160,835
Due after five years through ten years	16,991
Estimated fair value	$ 235,121

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