Condensed Consolidated Statements of Comprehensive (Loss)/Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract]
Net income	$ 8,431	$ 85,065
Other comprehensive (loss)/income, net of tax:
Cash flow hedges	(19,334)	10,060
Defined benefit and retiree healthcare plans	3,342	83
Other comprehensive (loss)/income	(15,992)	10,143
Comprehensive (loss)/income	$ (7,561)	$ 95,208

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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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