Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	$ 688,229	$ 688,229	$ 275,734
Gross Unrealized Gains	2,059	2,059	566
Gross Unrealized Losses	(3,188)	(3,188)	(1,681)
Available-for-sale securities, at fair value	687,100	687,100	274,619
Held-to-maturity Securities [Abstract]
Held-to-maturity, Amortized Cost	31,650	31,650	35,505
Gross Unrealized Gains	147	147	142
Gross Unrealized Losses	(562)	(562)	(803)
Held-to-maturity, fair value (in dollars)	31,235	31,235	34,844
Additional Information Abstract
Sale of available for sale securities		279,168
Available-for-sale Securities, Gross Realized Gains		777
Available-for-sale Securities, Gross Realized Losses		483
Available-for-sale Securities, Gross Realized Gain (Loss)	294	294
SBA guaranteed securities
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	102,239	102,239
Gross Unrealized Gains	379	379
Gross Unrealized Losses	(35)	(35)
Available-for-sale securities, at fair value	102,583	102,583
US Treasury and Government
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost			118,272
Gross Unrealized Gains			17
Gross Unrealized Losses			(403)
Available-for-sale securities, at fair value			117,886
Commercial
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	66,153	66,153
Gross Unrealized Gains	340	340
Gross Unrealized Losses	(107)	(107)
Available-for-sale securities, at fair value	66,386	66,386
Residential
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	288,027	288,027	99,876
Gross Unrealized Gains	1,246	1,246	452
Gross Unrealized Losses	(343)	(343)	(430)
Available-for-sale securities, at fair value	288,930	288,930	99,898
Held-to-maturity Securities [Abstract]
Held-to-maturity, Amortized Cost	13,001	13,001	14,358
Gross Unrealized Gains	140	140	140
Gross Unrealized Losses	(138)	(138)	(267)
Held-to-maturity, fair value (in dollars)	13,003	13,003	14,231
Commercial
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	31,194	31,194
Gross Unrealized Gains	71	71
Available-for-sale securities, at fair value	31,265	31,265
Residential
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	187,295	187,295	42,379
Gross Unrealized Gains	9	9	96
Gross Unrealized Losses	(2,467)	(2,467)	(563)
Available-for-sale securities, at fair value	184,837	184,837	41,912
Held-to-maturity Securities [Abstract]
Held-to-maturity, Amortized Cost	18,649	18,649	21,147
Gross Unrealized Gains	7	7	2
Gross Unrealized Losses	(424)	(424)	(536)
Held-to-maturity, fair value (in dollars)	18,232	18,232	20,613
Corporate debt securities
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	1,787	1,787	3,788
Gross Unrealized Gains	7	7	1
Gross Unrealized Losses			(14)
Available-for-sale securities, at fair value	1,794	1,794	3,775
Obligations of municipal subdivisions
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	236	236	236
Gross Unrealized Gains	7	7
Gross Unrealized Losses			(1)
Available-for-sale securities, at fair value	243	243	235
CRA qualified investment fund
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost	11,298	11,298	11,183
Gross Unrealized Losses	(236)	(236)	(270)
Available-for-sale securities, at fair value	$ 11,062	$ 11,062	$ 10,913

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

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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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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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