Balance Sheet Details (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Accounts receivable:
Accounts receivable	$ 93,962	$ 88,045
Allowance for doubtful accounts	5,734	5,307
Inventories:
Finished goods	153,581	129,091
Work in process	1,033	1,132
Raw materials	4,755	4,369
Repair parts	10,182	9,778
Operating supplies	1,263	1,489
Total inventories, less allowances of $3,911 and $4,808	170,814	145,859
Inventory allowances	3,911	4,808
Prepaid and other current assets:
Value added tax	2,707	1,834
Prepaid expenses	5,495	4,653
Refundable and prepaid income taxes	0	3,107
Derivative asset	0	107
Total prepaid and other current assets	8,202	9,701
Other assets:
Deposits	921	733
Finance fees - net of amortization	13,794	9,427
Deferred taxes	596	567
Other assets	3,856	3,947
Total other assets	19,167	14,674
Accrued liabilities:
Accrued incentives	25,300	16,621
Workers compensation	7,524	8,484
Medical liabilities	3,534	3,607
Interest	11,247	13,008
Commissions payable	1,954	1,137
Contingency liability	2,719	2,719
Other accrued liabilities	8,463	8,351
Total accrued liabilities	60,741	53,927
Other long-term liabilities:
Deferred liability	5,273	4,070
Derivative liability	0	298
Other long-term liabilities	4,669	5,041
Total other long-term liabilities	9,942	9,409
Trade receivables [Member]
Accounts receivable:
Accounts receivable	92,848	86,523
Other receivables [Member]
Accounts receivable:
Accounts receivable	$ 1,114	$ 1,522