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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 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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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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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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Amount of accumulated unrealized loss on 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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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Oct. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost		$ 275,379	$ 185,931
Gross Unrealized Gains		1,226	2,117
Gross Unrealized Losses		(584)	(483)
Available-for-sale securities, at fair value		276,021	187,565
Held-to-maturity Securities [Abstract]
Held-to-maturity, Amortized Cost		42,130	50,713
Gross Unrealized Gains		374	572
Gross Unrealized Losses		(508)	(560)
Held-to-maturity, fair value (in dollars)		41,996	50,725
Additional Information Abstract
Sale of available for sale securities		109,444	19,179	$ 6,736
Available-for-sale Securities, Gross Realized Gains	$ 195
US Treasury and Government [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost		90,032	57,108
Gross Unrealized Gains		3	21
Gross Unrealized Losses		(85)	(85)
Available-for-sale securities, at fair value		89,950	57,044
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost		129,752	100,002
Gross Unrealized Gains		1,137	2,022
Gross Unrealized Losses		(184)	(108)
Available-for-sale securities, at fair value		130,705	101,916
Held-to-maturity Securities [Abstract]
Held-to-maturity, Amortized Cost		15,002	16,823
Gross Unrealized Gains		320	485
Gross Unrealized Losses		(143)	(123)
Held-to-maturity, fair value (in dollars)		15,179	17,185
Collateralized Mortgage Backed Securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost		51,569	28,821
Gross Unrealized Gains		74	74
Gross Unrealized Losses		(314)	(290)
Available-for-sale securities, at fair value		51,329	28,605
Held-to-maturity Securities [Abstract]
Held-to-maturity, Amortized Cost		27,128	33,890
Gross Unrealized Gains		54	87
Gross Unrealized Losses		(365)	(437)
Held-to-maturity, fair value (in dollars)		26,817	33,540
Corporate debt securities
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost		3,790
Gross Unrealized Gains		4
Gross Unrealized Losses		(1)
Available-for-sale securities, at fair value		3,793
Obligations of municipal subdivisions
Available-for-sale Securities [Abstract]
Available-for-sale, Amortized Cost		236
Gross Unrealized Gains		8
Available-for-sale securities, at fair value		244
SP Bancorp Inc And Its Wholly Owned Subsidiary Share Plus Bank [Member]
Additional Information Abstract
Available-for-sale Securities, Gross Realized Gains			110
Available-for-sale Securities, Gross Realized Losses			$ 103
Patriot Bancshares Inc
Additional Information Abstract
Sale of available for sale securities	$ 76,500
Available-for-sale Securities, Gross Realized Gains		225
Available-for-sale Securities, Gross Realized Losses		$ 30