Investment Securities, Available-for-sale Securities, Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Amortized Cost [Abstract]
Due in one year or less	$ 15,124
Due in one year through five years	38,747
Due after five years through ten years	18
Amortized Cost	421,807	$ 573,432
Fair Value [Abstract]
Due in one year or less	15,267
Due in one year through five years	39,950
Due after five years through ten years	18
Fair Value	432,702	573,823
Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Amortized Cost [Abstract]
Securities, amortized cost	323,203
Amortized Cost	323,203	388,537
Fair Value [Abstract]
Securities, fair value	331,469
Fair Value	331,469	389,517
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized Cost [Abstract]
Securities, amortized cost	44,715
Amortized Cost	44,715	48,991
Fair Value [Abstract]
Securities, fair value	45,998
Fair Value	$ 45,998	$ 48,511

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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