Condensed Consolidated Statements of Comprehensive Income (Unuaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 131,901	$ 55,925	$ 336,262	$ 188,087
Available for sale securities:
Change in net unrealized (losses) gains	(1,029)	94	4,863	1,392
Less: reclassification adjustment for net (gains) losses included in net income	(928)	232	(1,220)	164
Net change (net of tax effect)	(1,957)	326	3,643	1,556
Cash flow hedges:
Change in unrealized gains (losses)	382	(2,348)	386	(5,692)
Less: reclassification adjustment for net losses included in net income	641	1,794	1,663	11,462
Net change (net of tax effect)	1,023	(554)	2,049	5,770
Other comprehensive (loss) income	(934)	(228)	5,692	7,326
Comprehensive income	$ 130,967	$ 55,697	$ 341,954	$ 195,413

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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