Securities, Held-to-maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Held-to-maturity [Abstract]
Amortized cost	$ 110,950	$ 120,121
Gross unrealized gains	0	21
Gross unrealized losses	(5,224)	(1,585)
Fair value	105,726	118,557
U.S. Government Agencies [Member]
Held-to-maturity [Abstract]
Amortized cost	28,171	28,169
Gross unrealized gains	0	0
Gross unrealized losses	(1,597)	(670)
Fair value	26,574	27,499
Municipal Bonds [Member]
Held-to-maturity [Abstract]
Amortized cost	5,245	5,322
Gross unrealized gains	0	15
Gross unrealized losses	(182)	(12)
Fair value	5,063	5,325
Mortgage-backed Securities [Member]
Held-to-maturity [Abstract]
Amortized cost	77,534	86,630
Gross unrealized gains	0	6
Gross unrealized losses	(3,445)	(903)
Fair value	$ 74,089	$ 85,733

Amount of investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

+ References

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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