Condensed Consolidated Statements of Comprehensive Income (Unuaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 144,259	$ 27,621
Available for sale securities:
Change in net unrealized (losses) gains	(4,542)	1,089
Less: reclassification adjustment for net losses (gains) included in net income	1,001	(375)
Net change (net of tax effect)	(3,541)	714
Gain (loss) on pension liability	0	(9)
Cash flow hedges:
Change in unrealized gains	692	1,993
Less: reclassification adjustment for net (gains) losses included in net income	(1,219)	1,672
Net change (net of tax effect)	(527)	3,665
Other comprehensive (loss) income	(4,068)	4,370
Comprehensive income	$ 140,191	$ 31,991

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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