Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statements Of Income And Comprehensive Income [Abstract]
Net income	$ 38,723us-gaap_NetIncomeLoss	$ 20,018us-gaap_NetIncomeLoss	$ 14,435us-gaap_NetIncomeLoss
Other comprehensive income/(loss):
Net unrealized holding gain/(loss) arising during period on investment securities available for sale, net of tax (benefit) of $3,969, ($4,421) and $215	7,371	(8,210)	399
Reclassification adjustment for gains on investment securities included in operations, net of tax of $48, $60 and $113	(90)	(111)	(209)
Net unrealized gains (losses) on cash flow hedges during the period, net of tax (benefit) of ($479), $765 and ($474)	(889)	1,420	(879)
Total other comprehensive income (loss)	6,392	(6,901)	(689)
Comprehensive income	$ 45,115us-gaap_ComprehensiveIncomeNetOfTax	$ 13,117us-gaap_ComprehensiveIncomeNetOfTax	$ 13,746us-gaap_ComprehensiveIncomeNetOfTax

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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