Investment Securities - Summary of Amortized Cost and Approximate Fair Values of Investment Securities Available for Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost	$ 278,333	$ 333,268
Available-for-sale, Gross Unrealized Gains	3,121	1,877
Available-for-sale, Gross Unrealized Losses, Less Than 12 Months	(316)	(1,596)
Available-for-sale, Gross Unrealized Losses, 12 Months or Longer	(433)	(813)
Available-for-sale, Fair Value	280,705	332,736
U.S. Government Sponsored Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost	79,713	104,591
Available-for-sale, Gross Unrealized Gains	188	11
Available-for-sale, Gross Unrealized Losses, Less Than 12 Months	(6)	(612)
Available-for-sale, Fair Value	79,895	103,990
Mortgage-backed Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost	10,000	181,857
Available-for-sale, Gross Unrealized Gains		940
Available-for-sale, Gross Unrealized Losses, Less Than 12 Months	(251)	(724)
Available-for-sale, Gross Unrealized Losses, 12 Months or Longer	(91)	(687)
Available-for-sale, Fair Value	9,658	181,386
Municipal Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost	30,384	36,820
Available-for-sale, Gross Unrealized Gains	844	926
Available-for-sale, Gross Unrealized Losses, Less Than 12 Months		(7)
Available-for-sale, Gross Unrealized Losses, 12 Months or Longer		(9)
Available-for-sale, Fair Value	31,228	37,730
Corporate Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale, Amortized Cost	158,236	10,000
Available-for-sale, Gross Unrealized Gains	2,089
Available-for-sale, Gross Unrealized Losses, Less Than 12 Months	(59)	(253)
Available-for-sale, Gross Unrealized Losses, 12 Months or Longer	(342)	(117)
Available-for-sale, Fair Value	$ 159,924	$ 9,630

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
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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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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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
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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

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