SECURITIES - Amortized Cost and Fair Value of Securities Available for Sale and Held for Investment (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Amortized cost and fair value of securities available for sale and held for investment
Gross Amortized Cost, Available for Sale	$ 858,434	$ 798,575
Gross Unrealized Gains, Available for Sale	11,812	3,027
Gross Unrealized Losses, Available for Sale	(3,633)	(10,836)
Fair Value, Available for Sale	866,613	790,766
Gross Amortized Cost, Held for Investment Securities	392,138	203,525
Gross Unrealized Gains, Held for Investment Securities	6,108	1,155
Gross Unrealized Losses, Held for Investment Securities	(982)	(1,867)
Fair Value, Held for Investment Securities	397,264	202,813
U.S. Treasury Securities and obligations of U.S. Government Sponsored Entities [Member]
Amortized cost and fair value of securities available for sale and held for investment
Gross Amortized Cost, Available for Sale	12,485	3,833
Gross Unrealized Gains, Available for Sale	333	78
Gross Unrealized Losses, Available for Sale	0	0
Fair Value, Available for Sale	12,818	3,911
Mortgage-backed securities of U.S. Government Sponsored Entities [Member]
Amortized cost and fair value of securities available for sale and held for investment
Gross Amortized Cost, Available for Sale	165,802	192,224
Gross Unrealized Gains, Available for Sale	3,268	847
Gross Unrealized Losses, Available for Sale	(96)	(1,322)
Fair Value, Available for Sale	168,974	191,749
Gross Amortized Cost, Held for Investment Securities	183,507	64,993
Gross Unrealized Gains, Held for Investment Securities	4,306	574
Gross Unrealized Losses, Held for Investment Securities	0	(16)
Fair Value, Held for Investment Securities	187,813	65,551
Collateralized Mortgage Obligations Of US Government Sponsored Entities [Member]
Amortized cost and fair value of securities available for sale and held for investment
Gross Amortized Cost, Available for Sale	251,419	242,620
Gross Unrealized Gains, Available for Sale	2,043	470
Gross Unrealized Losses, Available for Sale	(979)	(4,900)
Fair Value, Available for Sale	252,483	238,190
Gross Amortized Cost, Held for Investment Securities	160,377	89,265
Gross Unrealized Gains, Held for Investment Securities	1,618	581
Gross Unrealized Losses, Held for Investment Securities	(405)	(406)
Fair Value, Held for Investment Securities	161,590	89,440
Private mortgage backed securities [Member]
Amortized cost and fair value of securities available for sale and held for investment
Gross Amortized Cost, Available for Sale	32,720	32,558
Gross Unrealized Gains, Available for Sale	0	0
Gross Unrealized Losses, Available for Sale	(688)	(766)
Fair Value, Available for Sale	32,032	31,792
Fair Value, Held for Investment Securities	0
Private collateralized mortgage obligations [Member]
Amortized cost and fair value of securities available for sale and held for investment
Gross Amortized Cost, Available for Sale	73,371	77,965
Gross Unrealized Gains, Available for Sale	617	700
Gross Unrealized Losses, Available for Sale	(860)	(708)
Fair Value, Available for Sale	73,128	77,957
Gross Amortized Cost, Held for Investment Securities	6,760	7,967
Gross Unrealized Gains, Held for Investment Securities	1	0
Gross Unrealized Losses, Held for Investment Securities	(112)	(85)
Fair Value, Held for Investment Securities	6,649	7,882
Collateralized loan obligations [Member]
Amortized cost and fair value of securities available for sale and held for investment
Gross Amortized Cost, Available for Sale	124,663	124,477
Gross Unrealized Gains, Available for Sale	437	0
Gross Unrealized Losses, Available for Sale	(676)	(1,894)
Fair Value, Available for Sale	124,424	122,583
Gross Amortized Cost, Held for Investment Securities	41,494	41,300
Gross Unrealized Gains, Held for Investment Securities	183	0
Gross Unrealized Losses, Held for Investment Securities	(465)	(1,360)
Fair Value, Held for Investment Securities	41,212	39,940
Obligations of state and political subdivisions [Member]
Amortized cost and fair value of securities available for sale and held for investment
Gross Amortized Cost, Available for Sale	61,798	39,119
Gross Unrealized Gains, Available for Sale	2,688	882
Gross Unrealized Losses, Available for Sale	(52)	(110)
Fair Value, Available for Sale	64,434	39,891
Corporate and other debt securities [Member]
Amortized cost and fair value of securities available for sale and held for investment
Gross Amortized Cost, Available for Sale	75,552	44,652
Gross Unrealized Gains, Available for Sale	1,125	37
Gross Unrealized Losses, Available for Sale	(39)	(416)
Fair Value, Available for Sale	76,638	44,273
Fair Value, Held for Investment Securities	0
Commercial mortgage backed securities [Member]
Amortized cost and fair value of securities available for sale and held for investment
Gross Amortized Cost, Available for Sale	60,624	41,127
Gross Unrealized Gains, Available for Sale	1,301	13
Gross Unrealized Losses, Available for Sale	(243)	(720)
Fair Value, Available for Sale	61,682	$ 40,420
Fair Value, Held for Investment Securities	$ 0

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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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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-Publisher FASB
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-Section 50
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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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

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

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

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Fair value of investments in debt securities classified as held-to-maturity.

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