Scheduled Amortization Charges from Intangible Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Customer relationships
Expected Amortization Expense [Line Items]
2014	$ 75,307
2015	75,358
2016	75,358
2017	75,328
2018	75,312
Thereafter	1,037,146
Trade names
Expected Amortization Expense [Line Items]
2014	16,423
2015	16,418
2016	16,418
2017	16,407
2018	16,353
Thereafter	70,209
Provider network and practice management tools
Expected Amortization Expense [Line Items]
2014	26,394
2015	26,403
2016	26,353
2017	26,161
2018	26,075
Thereafter	23,130
Noncompetition and other agreements
Expected Amortization Expense [Line Items]
2014	43,142
2015	38,439
2016	29,256
2017	26,068
2018	18,902
Thereafter	47,639
Deferred debt financing costs
Expected Amortization Expense [Line Items]
2014	18,724
2015	17,097
2016	12,888
2017	9,715
2018	6,885
Thereafter	12,133
Lease agreements, net
Expected Amortization Expense [Line Items]
2014	(2,156)
2015	(2,107)
2016	(1,506)
2017	(1,185)
2018	(849)
Thereafter	(4,760)
Alliance and Product Supply Agreement liability
Expected Amortization Expense [Line Items]
2014	(5,330)
2015	$ (3,997)