Investment Securities, Available-for-sale Securities, Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Amortized Cost [Abstract]
Due in one year or less	$ 5,080
Due in one year through five years	170,836
Due after five years through ten years	50,055
Amortized Cost	635,841	$ 515,531
Fair Value [Abstract]
Due in one year or less	5,093
Due in one year through five years	170,638
Due after five years through ten years	50,039
Fair Value	633,540	501,463
Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Amortized Cost [Abstract]
Securities, amortized cost	356,376
Amortized Cost	356,376	271,386
Fair Value [Abstract]
Securities, fair value	354,679
Fair Value	354,679	262,032
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized Cost [Abstract]
Securities, amortized cost	53,494
Amortized Cost	53,494	58,376
Fair Value [Abstract]
Securities, fair value	53,091
Fair Value	$ 53,091	$ 56,475

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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