Condensed Consolidated Statements of Comprehensive Income/(Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income/(loss)	$ 18,568	$ (45,213)
Other comprehensive income/(loss), net of taxes:
Interest rate swaps (net of $(0.1) million and $0.3 million tax (expense)/benefit, respectively)	124	(488)
Qualified pension and post-employment benefit plans (net of $19.2 million and $0 million tax benefit, respectively)	(36,500)	671,024
Total other comprehensive income/(loss)	(36,376)	670,536
Comprehensive income/(loss)	$ (17,808)	$ 625,323