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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, 2020	Dec. 31, 2019
Amortized cost
Amortized cost	$ 1,017,254	$ 1,131,970
Estimated fair value
Estimated fair value	1,037,489	$ 1,138,352
Other Than Mortgage Backed Securities
Amortized cost
Due in one year or less	42,195
Due after one year through five years	50,689
Amortized cost	92,884
Estimated fair value
Due in one year or less	42,513
Due after one year through five years	51,767
Estimated fair value	$ 94,280

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- Definition

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

+ References

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