Unaudited Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 28,682	$ 27,670
Other Comprehensive Income, Net of Tax
Unrealized gains on available-for-sale securities	13,598	5,181
Reclassification adjustment for gains included in net income	(61)	(4)
Net unrealized gains on available-for-sale securities	13,537	5,177
Tax effect	(5,244)	(1,979)
Net of tax amount	8,293	3,198
Unrealized losses on derivatives used for cash flow hedges	(9,928)	(5,993)
Reclassification adjustment for losses included in net income	1,829	1,251
Net unrealized losses on derivatives used for cash flow hedges	(8,099)	(4,742)
Tax effect	3,138	1,827
Net of tax amount	(4,961)	(2,915)
Total other comprehensive income, net of tax	3,332	283
Total Comprehensive Income	$ 32,014	$ 27,953