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 (LOSS)
Net income (loss)	$ 15,623	$ (7,186)
Pension and post-retirement obligations:
Amortization of actuarial losses and prior service cost to earnings, net of tax	336	1,026
Derivative instruments designated as cash flow hedges:
Change in fair value of derivatives, net of tax	(11,944)	(6,689)
Cumulative adjustment upon adoption of ASU 2017-12		(576)
Reclassification of realized loss (gain) to earnings	1,608	(207)
Comprehensive income (loss)	5,623	(13,632)
Less: comprehensive income attributable to noncontrolling interest	76	79
Total comprehensive income (loss) attributable to common shareholders	$ 5,547	$ (13,711)

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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