Balance Sheet Details (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Accounts receivable:
Accounts receivable	$ 106,459	$ 94,549
Allowance for doubtful accounts	5,910	5,846
Inventories:
Finished goods	170,505	144,945
Work in process	1,321	1,615
Raw materials	4,869	4,558
Repair parts	11,122	10,550
Operating supplies	1,404	1,453
Total inventories, less loss provisions of $4,675 and $4,913	189,221	163,121
Inventory loss provisions	4,675	4,913
Prepaid and other current assets:
Value added tax	14,821	6,697
Prepaid expenses	8,826	8,396
Deferred income taxes	5,837	5,840
Prepaid income taxes	3,410	3,511
Derivative asset	274	394
Total prepaid and other current assets	33,168	24,838
Other assets:
Deposits	912	919
Finance fees — net of amortization	7,261	10,472
Other assets	2,334	2,143
Total other assets	10,507	13,534
Accrued liabilities:
Accrued incentives	25,451	17,830
Workers compensation	6,838	7,108
Medical liabilities	3,718	3,433
Interest	3,905	3,331
Commissions payable	1,079	1,067
Withholdings and other non-income tax accruals	2,396	1,929
Other accrued liabilities	7,341	6,720
Total accrued liabilities	50,728	41,418
Other long-term liabilities:
Deferred liability	7,001	7,424
Derivative liability	68	2,073
Other long-term liabilities	4,925	4,277
Total other long-term liabilities	11,994	13,774
Trade receivables
Accounts receivable:
Accounts receivable	104,493	87,499
Other receivables [Member]
Accounts receivable:
Accounts receivable	$ 1,966	$ 7,050