Details of Certain Balance Sheet Accounts - Accrued Expenses (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Details Of Certain Balance Sheet Accounts [Abstract]
Health insurance	$ 12,200,000	$ 9,500,000
Workers' compensation	16,500,000	16,300,000
Legal and other settlements	6,200,000	6,900,000
Lease liability	1,800,000	1,200,000
Charity care	600,000	600,000
Other accrued expenses	16,300,000	15,600,000
Estimated Medicare CAP liability	4,000,000	4,800,000
Accrued expenses	$ 57,572,000	$ 54,855,000