Accrued Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Accrued Liabilities [Abstract]
Payroll and other compensation	$ 35,008	$ 41,070
Pension and other postretirement benefits	8,184	8,405
Other	53,172	42,775
Accrued liabilities	$ 96,364	$ 92,250