Supplemental Financial Information - Noncash Investing and Financing Activities (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule Of Supplemental Cash Flow [Line Items]
Accrued but unpaid capital expenditures at December 31	$ 56,595	$ 37,325	$ 28,947
Income tax benefits related to exercise of stock options	1,083	863	1,078
Cash interest payments, including amounts capitalized (1)	46,156	71,884	84,370
U.S federal [Member]
Cash income taxes paid, net of refunds:
Cash income taxes paid, net of refunds	71,000	94,843	427,504
Foreign [Member]
Cash income taxes paid, net of refunds:
Cash income taxes paid, net of refunds	72,249	150,465	128,447
State [Member]
Cash income taxes paid, net of refunds:
Cash income taxes paid, net of refunds	$ 243	$ 210	$ 111