Condensed Consolidated Statements of Comprehensive Income (Unuaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 110,348	$ 144,259
Available for sale securities:
Change in net unrealized gains (losses)	2,188	(4,542)
Less: reclassification adjustment for net (gains) losses included in net income	(558)	1,001
Net change (net of tax effect)	1,630	(3,541)
Cash flow hedges:
Change in unrealized gains	147	692
Less: reclassification adjustment for net losses (gains) included in net income	894	(1,219)
Net change (net of tax effect)	1,041	(527)
Other comprehensive income (loss)	2,671	(4,068)
Comprehensive income	$ 113,019	$ 140,191

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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