Securities - AFS and HTM, Amortized Cost and FV (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Available for sale
Amortized Cost	$ 762,984	$ 598,198
Gross Unrealized Gains	7,760	6,895
Gross Unrealized Losses	(5,202)	(7,086)
Fair Value	765,542	598,007
Held to maturity
Amortized cost	368,031	351,831
Unrealized Gains	1,071	313
Unrealized Losses	(4,980)	(7,056)
Held to maturity, fair value	364,122	345,088
US Treasury Securities
Available for sale
Amortized Cost	22,751	31,701
Gross Unrealized Gains	168	144
Gross Unrealized Losses	(39)	(44)
Fair Value	22,880	31,801
Bonds
Available for sale
Amortized Cost	100,289	121,838
Gross Unrealized Gains	851	881
Gross Unrealized Losses	(133)	(67)
Fair Value	101,007	122,652
Held to maturity
Amortized cost	40,515	40,513
Unrealized Gains	28
Unrealized Losses	(891)	(1,287)
Held to maturity, fair value	39,652	39,226
Residential mortgage-backed Securities
Available for sale
Amortized Cost	247,272	135,371
Gross Unrealized Gains	940	708
Gross Unrealized Losses	(2,304)	(2,941)
Fair Value	245,908	133,138
Held to maturity
Amortized cost	16,973	19,606
Unrealized Gains	198	13
Unrealized Losses		(6)
Held to maturity, fair value	17,171	19,613
Commercial mortgage-backed securities
Available for sale
Amortized Cost	12,091	8,771
Gross Unrealized Gains	78	2
Gross Unrealized Losses	(24)	(58)
Fair Value	12,145	8,715
Held to maturity
Amortized cost	71,613	31,767
Unrealized Gains	404	102
Unrealized Losses	(510)	(593)
Held to maturity, fair value	71,507	31,276
Collateralized mortgage obligations
Available for sale
Amortized Cost	222,187	117,879
Gross Unrealized Gains	203	29
Gross Unrealized Losses	(2,656)	(3,206)
Fair Value	219,734	114,702
Held to maturity
Amortized cost	183,926	217,954
Unrealized Gains	152	128
Unrealized Losses	(2,550)	(3,372)
Held to maturity, fair value	181,528	214,710
Corporate securities
Available for sale
Amortized Cost	72,266	76,866
Gross Unrealized Gains	2,489	2,354
Gross Unrealized Losses	(2)	(91)
Fair Value	74,753	79,129
States and political subdivisions
Available for sale
Amortized Cost	66,173	86,353
Gross Unrealized Gains	1,493	1,498
Gross Unrealized Losses	(39)	(336)
Fair Value	67,627	87,515
Held to maturity
Amortized cost	55,004	41,991
Unrealized Gains	289	70
Unrealized Losses	(1,029)	(1,798)
Held to maturity, fair value	54,264	40,263
Commercial mortgage-backed securities.
Available for sale
Amortized Cost	499	499
Gross Unrealized Gains	6	16
Fair Value	505	515
Equity securities
Available for sale
Amortized Cost	19,456	18,920
Gross Unrealized Gains	1,532	1,263
Gross Unrealized Losses	(5)	(343)
Fair Value	$ 20,983	$ 19,840

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

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