Securities - Amortized Cost and Estimated Fair Value of Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Securities available-for-sale:
Amortized Cost	$ 384,578	$ 201,497
Gross Unrealized Gains	2,863	5,126
Gross Unrealized Losses	(2,362)	(288)
Securities available-for-sale	385,079	206,335
Agency mortgage-backed securities
Securities available-for-sale:
Amortized Cost	324,077	150,570
Gross Unrealized Gains	2,457	3,867
Gross Unrealized Losses	(2,304)	(265)
Securities available-for-sale	324,230	154,172
U.S. Treasury
Securities available-for-sale:
Amortized Cost	30,047
Gross Unrealized Losses	(44)
Securities available-for-sale	30,003
Trust preferred securities
Securities available-for-sale:
Amortized Cost	15,000	15,000
Gross Unrealized Gains	132	300
Securities available-for-sale	15,132	15,300
U.S. Government sponsored entities
Securities available-for-sale:
Amortized Cost	9,042
Gross Unrealized Gains	13
Gross Unrealized Losses	(14)
Securities available-for-sale	9,041
Corporate bonds
Securities available-for-sale:
Amortized Cost	6,412	35,927
Gross Unrealized Gains	261	959
Gross Unrealized Losses		(23)
Securities available-for-sale	$ 6,673	$ 36,863

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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