Securities, Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Available-for-sale [Abstract]
Amortized cost	$ 341,207	$ 383,893
Gross unrealized gains	1,010	3,095
Gross unrealized losses	(14,768)	(5,453)
Fair value	327,449	381,535
U.S. Treasuries [Member]
Available-for-sale [Abstract]
Amortized cost	16,597	19,490
Gross unrealized gains	0	0
Gross unrealized losses	(2)	(4)
Fair value	16,595	19,486
U.S. Government Agencies [Member]
Available-for-sale [Abstract]
Amortized cost	161,409	200,052
Gross unrealized gains	0	0
Gross unrealized losses	(9,579)	(4,069)
Fair value	151,830	195,983
Corporate Debt Securities [Member]
Available-for-sale [Abstract]
Amortized cost	77,181	91,770
Gross unrealized gains	57	661
Gross unrealized losses	(3,109)	(946)
Fair value	74,129	91,485
Mutual Funds or Other Equity Securities [Member]
Available-for-sale [Abstract]
Amortized cost	478	500
Gross unrealized gains	0	0
Gross unrealized losses	0	(7)
Fair value	478	493
Municipal Bonds [Member]
Available-for-sale [Abstract]
Amortized cost	34,633	37,210
Gross unrealized gains	953	2,434
Gross unrealized losses	(363)	(75)
Fair value	35,223	39,569
Collateralized Mortgage Obligations [Member]
Available-for-sale [Abstract]
Amortized cost	977	1,191
Gross unrealized gains	0	0
Gross unrealized losses	(28)	(6)
Fair value	949	1,185
Mortgage-backed Securities [Member]
Available-for-sale [Abstract]
Amortized cost	49,932	33,680
Gross unrealized gains	0	0
Gross unrealized losses	(1,687)	(346)
Fair value	$ 48,245	$ 33,334

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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-Section 50
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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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-Publisher FASB
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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