Accrued Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Schedule of Accrued Liabilities [Line Items]
Accrued compensation	$ 33,312	$ 31,325
Accrued insurance	30,376	26,449
Accrued income taxes	6,178	2,703
Accrued other taxes	22,132	15,016
Accrued interest	9,037	8,934
Accrued professional services liabilities	2,011	4,377
Accrued product reimbursement	9,361	23,907
Accrued liabilities-other	28,114	21,644
Total accrued liabilities	$ 140,521	$ 134,355