Investment Securities, Available-for-sale Securities, Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Amortized Cost [Abstract]
Due in one year or less	$ 5,049
Due in one year through five years	150,845
Due after five years through ten years	50,055
Amortized Cost	662,642	$ 515,531
Fair Value [Abstract]
Due in one year or less	5,060
Due in one year through five years	150,454
Due after five years through ten years	50,109
Fair Value	662,759	501,463
Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Amortized Cost [Abstract]
Securities, amortized cost	405,677
Amortized Cost	405,677	271,386
Fair Value [Abstract]
Securities, fair value	406,166
Fair Value	406,166	262,032
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized Cost [Abstract]
Securities, amortized cost	51,016
Amortized Cost	51,016	58,376
Fair Value [Abstract]
Securities, fair value	50,970
Fair Value	$ 50,970	$ 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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