Other Non-Current Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Composition of other non-current liabilities
Deferred revenue	$ 1,614	$ 1,000
Environmental and legal matters	13,459	13,205
Deferred compensation liability	41,665	31,790
Pension liability	37,855	37,595
Other non-current liabilities	4,074	5,226
Total other non-current liabilities	$ 98,667	$ 88,816