Investment Securities, Available-for-sale Securities, Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Amortized Cost [Abstract]
Due in one year or less	$ 10,062
Due in one year through five years	83,558
Due after five years through ten years	10,018
Amortized Cost	493,198	$ 573,432
Fair Value [Abstract]
Due in one year or less	10,104
Due in one year through five years	84,189
Due after five years through ten years	10,038
Fair Value	503,166	573,823
Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Amortized Cost [Abstract]
Securities, amortized cost	343,168
Amortized Cost	343,168	388,537
Fair Value [Abstract]
Securities, fair value	352,067
Fair Value	352,067	389,517
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized Cost [Abstract]
Securities, amortized cost	46,392
Amortized Cost	46,392	48,991
Fair Value [Abstract]
Securities, fair value	46,768
Fair Value	$ 46,768	$ 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).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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