Condensed Consolidated Statements of Comprehensive Income (Unuaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 158,857	$ 126,720	$ 409,949	$ 263,170
Available for sale securities:
Change in net unrealized gains (losses)	816	60	(3,394)	1,500
Less: reclassification adjustment for net losses (gains) included in net income	62	120	1,307	(340)
Net change (net of tax effect)	878	180	(2,087)	1,160
Loss on pension liability	0	272	0	263
Cash flow hedges:
Change in unrealized (losses) gains	(1,636)	776	(4,367)	4,663
Less: reclassification adjustment for net losses (gains) included in net income	1,185	(1,116)	(1,031)	551
Net change (net of tax effect)	(451)	(340)	(5,398)	5,214
Other comprehensive (loss) income	427	112	(7,485)	6,637
Comprehensive income	$ 159,284	$ 126,832	$ 402,464	$ 269,807

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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