Securities (Schedule of Contractual Maturities of Investment Securities Available for Sale) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Abstract]
Due within one year, Amortized Cost	$ 53,099
Due after one year through five years, Amortized Cost	389,269
Due after five years through ten years, Amortized Cost	1,894,385
Due after ten years, Amortized Cost	1,154,554
Debt securities available-for-sale, amortized cost	3,491,307	$ 3,703,096
Due within one year, Fair Value	53,800
Due after one year through five years, Fair Value	409,099
Due after five years through ten years, Fair Value	2,038,033
Due after ten years, Fair Value	1,192,855
Debt securities available for sale at fair value	$ 3,693,787	$ 3,746,142

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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