Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ 36,759	$ (111,601)	$ (166,357)	$ (127,021)
Pension and postretirement plans:
Amortization of prior service cost, net of tax of ($42), $0, ($89) and $0, respectively	(71)	0	(149)	0
Amortization of net loss, including settlement charges, net of tax of $0, $309, $1,168 and $1,305, respectively	0	576	1,890	2,427
Current period change in fair value of pension and postretirement plans, net of tax of $0, $0, ($6) and $0, respectively	0	0	(9)	0
Total pension and postretirement plans	(71)	576	1,732	2,427
Comprehensive Income (Loss)	$ 36,688	$ (111,025)	$ (164,625)	$ (124,594)