CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net Income	$ 15,647	$ (3,772)	$ 67,890	$ 39,709
Other comprehensive (loss) income, net of tax:
Reclassification of net gains on derivative instruments to net income	(183)	(178)	(549)	(552)
Postretirement medical liability adjustment	0	0	0	205
Foreign currency translation	(54)	(79)	81	(80)
Total Other Comprehensive Loss	(237)	(257)	(468)	(427)
Comprehensive Income	$ 15,410	$ (4,029)	$ 67,422	$ 39,282