Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Consolidated Statements of Comprehensive Income
Net income	$ 9,255	$ 8,177
Unrealized gains on securities available-for-sale:
Unrealized gains arising during the period (net of tax of $1,012 and $1,091, respectively)	1,880	2,026
Unrealized gains on hedging instruments:
Unrealized (losses) gains arising during the period (net of tax of ($9) and $12, respectively)	(19)	21
Other comprehensive income	1,861	2,047
Comprehensive income	$ 11,116us-gaap_ComprehensiveIncomeNetOfTax	$ 10,224us-gaap_ComprehensiveIncomeNetOfTax

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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