Securities - Amortized Cost and Estimated Fair Value of Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Securities available-for-sale:
Amortized Cost	$ 382,686	$ 384,578
Gross Unrealized Gains	7,749	2,863
Gross Unrealized Losses		(2,362)
Securities available-for-sale	390,435	385,079
Agency mortgage-backed securities
Securities available-for-sale:
Amortized Cost	366,690	324,077
Gross Unrealized Gains	6,770	2,457
Gross Unrealized Losses		(2,304)
Securities available-for-sale	373,460	324,230
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	938	132
Securities available-for-sale	15,938	15,132
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	996	6,412
Gross Unrealized Gains	41	261
Securities available-for-sale	$ 1,037	$ 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
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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-Publisher FASB
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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