Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 12,574us-gaap_NetIncomeLoss	$ 749us-gaap_NetIncomeLoss
Unrealized gain on available for sale securities:
Unrealized gain arising during the period	1,928	1,023
Reclassification adjustment for loss (gain) included in net income	1	(507)
Total change in unrealized gain on available for sale securities	1,929	516
Unrealized loss on cash flow hedge:
Unrealized loss arising during the period	(104)	(217)
Total change in unrealized loss on cash flow hedge	(104)	(217)
Total other comprehensive income	1,825	299
Comprehensive income	$ 14,399us-gaap_ComprehensiveIncomeNetOfTax	$ 1,048us-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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