Condensed Consolidated Statements of Comprehensive Income (Unuaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 27,621	$ 83,463
Available for sale securities:
Change in net unrealized gains	1,089	4,099
Less: reclassification adjustment for net gains included in net income	(375)	(22)
Net change (net of tax effect)	714	4,077
Loss on pension liability	9	0
Cash flow hedges:
Change in unrealized gains	1,993	2,222
Less: reclassification adjustment for net losses included in net income	1,672	1,165
Net change (net of tax effect)	3,665	3,387
Other comprehensive income	4,370	7,464
Comprehensive income	$ 31,991	$ 90,927