CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net income (loss):	$ 5,990	$ (330,308)	$ (35,905)
Other comprehensive income, net of tax:
Prior service cost arising during the period		(1,597)	(910)
Net loss arising during the period	(2,485)	(3,558)	(260)
Amortization and curtailment of prior service cost included in net periodic cost	2,503	1,106	1,083
Amortization and settlement related to the pension plan included in net periodic cost	1,210	2,274	1,716
Amortization and settlement related to the post retirement medical plan included in net periodic cost		2,441	383
Total other comprehensive income, net of tax	1,228	666	2,012
Total comprehensive income (loss)	$ 7,218	$ (329,642)	$ (33,893)