Accounts Payable and Accrued Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Carrying value of accounts payable and accrued liabilities
Accounts payable	$ 227,571	$ 212,084
Wages, severance and related taxes	41,938	40,133
Employee benefits	16,244	17,390
Accrued rebates	34,736	32,138
Other (individual items less than 5% of total current liabilities)	61,077	56,179
Accounts payable and accrued liabilities	$ 381,566	$ 357,924