Securities - AFS and HTM, Amortized Cost and FV (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Available for sale
Amortized Cost	$ 755,290	$ 598,198
Gross Unrealized Gains	7,112	6,895
Gross Unrealized Losses	(6,856)	(7,086)
Fair Value	755,546	598,007
Held to maturity
Amortized cost	337,357	351,831
Unrealized Gains	481	313
Unrealized Losses	(6,451)	(7,056)
Held to maturity, fair value	331,387	345,088
US Treasury Securities
Available for sale
Amortized Cost	101,683	31,701
Gross Unrealized Gains	156	144
Gross Unrealized Losses	(44)	(44)
Fair Value	101,795	31,801
Bonds
Available for sale
Amortized Cost	100,984	121,838
Gross Unrealized Gains	857	881
Gross Unrealized Losses	(167)	(67)
Fair Value	101,674	122,652
Held to maturity
Amortized cost	40,513	40,513
Unrealized Gains	6
Unrealized Losses	(1,192)	(1,287)
Held to maturity, fair value	39,327	39,226
Residential mortgage-backed Securities
Available for sale
Amortized Cost	211,934	135,371
Gross Unrealized Gains	757	708
Gross Unrealized Losses	(3,018)	(2,941)
Fair Value	209,673	133,138
Held to maturity
Amortized cost	18,717	19,606
Unrealized Gains	128	13
Unrealized Losses	(11)	(6)
Held to maturity, fair value	18,834	19,613
Commercial mortgage-backed securities
Available for sale
Amortized Cost	8,719	8,771
Gross Unrealized Gains	1	2
Gross Unrealized Losses	(40)	(58)
Fair Value	8,680	8,715
Held to maturity
Amortized cost	31,604	31,767
Unrealized Gains	102	102
Unrealized Losses	(554)	(593)
Held to maturity, fair value	31,152	31,276
Collateralized mortgage obligations
Available for sale
Amortized Cost	157,656	117,879
Gross Unrealized Gains	31	29
Gross Unrealized Losses	(3,243)	(3,206)
Fair Value	154,444	114,702
Held to maturity
Amortized cost	205,176	217,954
Unrealized Gains	115	128
Unrealized Losses	(3,077)	(3,372)
Held to maturity, fair value	202,214	214,710
Corporate securities
Available for sale
Amortized Cost	76,076	76,866
Gross Unrealized Gains	2,421	2,354
Gross Unrealized Losses	(40)	(91)
Fair Value	78,457	79,129
States and political subdivisions
Available for sale
Amortized Cost	78,644	86,353
Gross Unrealized Gains	1,635	1,498
Gross Unrealized Losses	(229)	(336)
Fair Value	80,050	87,515
Held to maturity
Amortized cost	41,347	41,991
Unrealized Gains	130	70
Unrealized Losses	(1,617)	(1,798)
Held to maturity, fair value	39,860	40,263
Commercial mortgage-backed securities
Available for sale
Amortized Cost	499	499
Gross Unrealized Gains	11	16
Fair Value	510	515
Equity securities
Available for sale
Amortized Cost	19,095	18,920
Gross Unrealized Gains	1,243	1,263
Gross Unrealized Losses	(75)	(343)
Fair Value	$ 20,263	$ 19,840

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

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