Commitments - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Commitments and Contingencies Disclosure [Line Items]
Prepaid land leasing arrangements	2
Rent expense	$ 57,260	$ 58,978	$ 54,024
Short term committed purchase obligations	86,929
Contribution by employer for employee saving plan	$ 7,523	$ 6,312	$ 6,127
Buildings
Commitments and Contingencies Disclosure [Line Items]
Terms of operating leases expiring year	Jan. 01, 2021
Land
Commitments and Contingencies Disclosure [Line Items]
Terms of operating leases expiring year	Jan. 01, 2057