Schedule 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]
Trade accounts payable	$ 58,200	$ 45,805
Accrued salaries and wages	58,810	42,345
Accrued dividends	56,306	452
Accrued workers' compensation and auto liability	8,409	8,455
Accrued litigation	6,170	8,643
Accrued employee medical insurance	9,658	10,480
Accrued property taxes	24,721	24,399
Accrued interest	6,331	3,509
Other	23,672	20,441
Accounts payable and accrued expenses, total	$ 252,277	$ 164,529