Condensed Consolidated Statements of Comprehensive Income (Unuaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 106,833	$ 108,829	$ 251,092	$ 136,450
Available for sale securities:
Change in net unrealized gains (losses)	332	350	(4,210)	1,440
Less: reclassification adjustment for net losses (gains) included in net income	243	(85)	1,244	(460)
Net change (net of tax effect)	575	265	(2,966)	980
Loss on pension liability	0	0	0	(9)
Cash flow hedges:
Change in unrealized (losses) gains	(3,422)	1,884	(2,730)	3,876
Less: reclassification adjustment for net (gains) losses included in net income	(997)	6	(2,216)	1,678
Net change (net of tax effect)	(4,419)	1,890	(4,946)	5,554
Other comprehensive (loss) income	(3,844)	2,155	(7,912)	6,525
Comprehensive income	$ 102,989	$ 110,984	$ 243,180	$ 142,975

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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