Accounts Payable and Accrued Expenses - Components of Accounts Payable and Accrued Expenses (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Accounts Payable and Accrued Liabilities [Line Items]
Accounts payable	$ 504,745	$ 508,812
Payroll and benefits, including incentive compensation	84,050	155,016
Health insurance, workers' compensation and other insurance costs	49,087	59,269
Current derivative liability	318	19,601
Other accrued liabilities	123,088	170,933
Total	$ 761,288	$ 913,631