Investment Securities, Available-for-sale Securities, Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Amortized Cost [Abstract]
Due in one year or less	$ 5,165
Due in one year through five years	175,796
Due after five years through ten years	61
Amortized Cost	555,946	$ 515,531
Fair Value [Abstract]
Due in one year or less	5,166
Due in one year through five years	174,180
Due after five years through ten years	61
Fair Value	546,466	501,463
Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Amortized Cost [Abstract]
Securities, amortized cost	318,864
Amortized Cost	318,864	271,386
Fair Value [Abstract]
Securities, fair value	312,946
Fair Value	312,946	262,032
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized Cost [Abstract]
Securities, amortized cost	56,060
Amortized Cost	56,060	58,376
Fair Value [Abstract]
Securities, fair value	54,113
Fair Value	$ 54,113	$ 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
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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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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Amortized cost of investment in debt security measured at fair value with change recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next 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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping.

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