Segments and Geographic Area Analysis - Revenues by Geographic Area Presented by Attributing Revenues to Individual Country (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenues from External Customers and Long-Lived Assets [Line Items]
Entity-Wide Disclosure on Geographic Areas, Revenue from External Customers Attributed to Individual Foreign Countries, Amount									$ 2,812,547	$ 2,999,038	$ 2,687,429
Total revenues	750,537	729,141	738,188	768,642	748,357	878,177	889,496	806,389	2,986,508	3,322,419	3,322,974
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Entity-Wide Disclosure on Geographic Areas, Revenue from External Customers Attributed to Entity's Country of Domicile									173,961	323,381	635,545
South America [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Entity-Wide Disclosure on Geographic Areas, Revenue from External Customers Attributed to Individual Foreign Countries, Amount									1,427,927	1,736,798	1,308,641
Europe/Africa/Mediterranean [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Entity-Wide Disclosure on Geographic Areas, Revenue from External Customers Attributed to Individual Foreign Countries, Amount									662,995	749,128	601,122
Australia/Asia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Entity-Wide Disclosure on Geographic Areas, Revenue from External Customers Attributed to Individual Foreign Countries, Amount									524,957	451,364	641,372
Mexico [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Entity-Wide Disclosure on Geographic Areas, Revenue from External Customers Attributed to Individual Foreign Countries, Amount									$ 196,668	$ 61,748	$ 136,294