Securities - Amortized Cost and Estimated Fair Value of Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Securities available-for-sale:
Amortized Cost	$ 443,382	$ 384,578
Gross Unrealized Gains	5,230	2,863
Gross Unrealized Losses	(72)	(2,362)
Securities available-for-sale	448,540	385,079
Agency mortgage-backed securities
Securities available-for-sale:
Amortized Cost	388,282	324,077
Gross Unrealized Gains	4,543	2,457
Gross Unrealized Losses	(72)	(2,304)
Securities available-for-sale	392,753	324,230
U.S. Treasury
Securities available-for-sale:
Amortized Cost	30,054	30,047
Gross Unrealized Gains	278
Gross Unrealized Losses		(44)
Securities available-for-sale	30,332	30,003
Trust preferred securities
Securities available-for-sale:
Amortized Cost	15,000	15,000
Gross Unrealized Gains	225	132
Securities available-for-sale	15,225	15,132
U.S. Government sponsored entities
Securities available-for-sale:
Amortized Cost	9,041	9,042
Gross Unrealized Gains	140	13
Gross Unrealized Losses		(14)
Securities available-for-sale	9,181	9,041
Corporate bonds
Securities available-for-sale:
Amortized Cost	1,005	6,412
Gross Unrealized Gains	44	261
Securities available-for-sale	$ 1,049	$ 6,673

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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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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-Publisher FASB
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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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-Publisher FASB
-Name Accounting Standards Codification
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