Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	$ 558,323	$ 275,734
Gross Unrealized Gains	497	566
Gross Unrealized Losses	(3,188)	(1,681)
Available-for-sale securities, at fair value	555,632	274,619
Held-to-maturity Securities [Abstract]
Held-to-maturity, Amortized Cost	33,836	35,505
Gross Unrealized Gains	121	142
Gross Unrealized Losses	(711)	(803)
Held-to-maturity, fair value (in dollars)	33,246	34,844
US Treasury and Government [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	262,649	118,272
Gross Unrealized Gains	17	17
Gross Unrealized Losses	(589)	(403)
Available-for-sale securities, at fair value	262,077	117,886
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	239,892	99,876
Gross Unrealized Gains	471	452
Gross Unrealized Losses	(1,823)	(430)
Available-for-sale securities, at fair value	238,540	99,898
Held-to-maturity Securities [Abstract]
Held-to-maturity, Amortized Cost	13,986	14,358
Gross Unrealized Gains	120	140
Gross Unrealized Losses	(246)	(267)
Held-to-maturity, fair value (in dollars)	13,860	14,231
Collateralized Mortgage Backed Securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	40,519	42,379
Gross Unrealized Gains		96
Gross Unrealized Losses	(477)	(563)
Available-for-sale securities, at fair value	40,042	41,912
Held-to-maturity Securities [Abstract]
Held-to-maturity, Amortized Cost	19,850	21,147
Gross Unrealized Gains	1	2
Gross Unrealized Losses	(465)	(536)
Held-to-maturity, fair value (in dollars)	19,386	20,613
Corporate debt securities
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	3,787	3,788
Gross Unrealized Gains	7	1
Gross Unrealized Losses		(14)
Available-for-sale securities, at fair value	3,794	3,775
Obligations of municipal subdivisions
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	236	236
Gross Unrealized Gains	2
Gross Unrealized Losses		(1)
Available-for-sale securities, at fair value	238	235
CRA qualified investment fund
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	11,240	11,183
Gross Unrealized Losses	(299)	(270)
Available-for-sale securities, at fair value	$ 10,941	$ 10,913

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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