Condensed Consolidated Statements of Comprehensive Income (Unuaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 270,857	$ 158,857	$ 474,700	$ 409,949
Available for sale securities:
Change in net unrealized gains (losses)	57	816	2,859	(3,394)
Less: reclassification adjustment for net losses (gains) included in net income	7	62	(577)	1,307
Net change (net of tax effect)	64	878	2,282	(2,087)
Cash flow hedges:
Change in unrealized losses	(1,774)	(1,636)	(1,439)	(4,367)
Less: reclassification adjustment for net (gains) losses included in net income	(162)	1,185	829	(1,031)
Net change (net of tax effect)	(1,936)	(451)	(610)	(5,398)
Other comprehensive (loss) income	(1,872)	427	1,672	(7,485)
Comprehensive income	$ 268,985	$ 159,284	$ 476,372	$ 402,464

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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