CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME/(LOSS) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net income	$ 33,019	$ 10,897
Other comprehensive (loss)/income, net of tax:
Net change in unrealized losses on cash flow hedges	(14,985)	(3,178)
Defined benefit pension and other postretirement benefit plans:
Net change in unrecognized prior service costs	72	(26)
Net change in unrecognized actuarial losses	521	(173)
Other comprehensive loss, net of tax	(14,392)	(3,377)
Comprehensive income	$ 18,627	$ 7,520