Condensed Consolidated Statements of Comprehensive Income [Unaudited] (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net income	$ 6,646,000us-gaap_NetIncomeLoss	$ 3,580,000us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Unrealized holding gains on securities available for sale	2,873,000	2,604,000
Fair value of interest rate swap	(197,000)	14,000
	2,676,000	2,618,000
Tax effect of unrealized holding gains (losses) on securities available for sale	(997,000)	(906,000)
Tax effect of fair value of interest rate swap	69,000	(5,000)
	(928,000)	(911,000)
Other comprehensive income, net of tax effect	1,748,000	1,707,000
Comprehensive income	$ 8,394,000us-gaap_ComprehensiveIncomeNetOfTax	$ 5,287,000us-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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Amount before tax of other comprehensive income (loss) attributable to parent entity.

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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