Balance Sheet Details (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Accounts receivable:
Accounts receivable	$ 87,046	$ 94,549
Allowance for doubtful accounts	6,216	5,846
Inventories:
Finished goods	156,237	144,945
Work in process	1,650	1,615
Raw materials	4,300	4,558
Repair parts	10,766	10,550
Operating supplies	1,226	1,453
Total inventories, less loss provisions of $4,784 and $4,913	174,179	163,121
Inventory loss provisions	4,784	4,913
Prepaid and other current assets:
Value added tax	9,732	6,697
Prepaid expenses	10,590	8,396
Deferred income taxes	5,840	5,840
Prepaid income taxes	5,164	3,511
Derivative asset	573	394
Total prepaid and other current assets	31,899	24,838
Other assets:
Deposits	944	919
Finance fees — net of amortization	10,023	10,472
Other assets	2,167	2,143
Total other assets	13,134	13,534
Accrued liabilities:
Accrued incentives	15,801	17,830
Workers compensation	7,178	7,108
Medical liabilities	3,246	3,433
Interest	10,138	3,331
Commissions payable	856	1,067
Withholdings and other non-income tax accruals	2,829	1,929
Other accrued liabilities	6,851	6,720
Total accrued liabilities	46,899	41,418
Other long-term liabilities:
Deferred liability	7,863	7,424
Derivative liability	0	2,073
Other long-term liabilities	3,869	4,277
Total other long-term liabilities	11,732	13,774
Trade receivables
Accounts receivable:
Accounts receivable	85,472	87,499
Other receivables [Member]
Accounts receivable:
Accounts receivable	$ 1,574	$ 7,050