Debt - Additional Information 1 (Detail) (USD $)	3 Months Ended			3 Months Ended							1 Months Ended		3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Mar. 31, 2013 Minimum [Member] BasisPoint	Mar. 31, 2013 Maximum [Member] BasisPoint	Mar. 31, 2013 Term Loan under the Senior Credit Agreement [Member] 2012-1 Term Loan A [Member] First eight quarters [Member]	Mar. 31, 2013 Term Loan under the Senior Credit Agreement [Member] 2012-1 Term Loan A [Member] Next four quarters [Member]	Mar. 31, 2013 Term Loan under the Senior Credit Agreement [Member] 2012-1 Term Loan A [Member] Each quarter thereafter [Member]	Mar. 31, 2013 Term Loan under the Senior Credit Agreement [Member] 2012-1 Term Loan [Member]	Mar. 31, 2013 Term Loan under the Senior Credit Agreement [Member] 2011 Term Loan B [Member] BasisPoint	Apr. 24, 2013 Term Loan under the Senior Credit Agreement [Member] 2011 Term Loan B [Member] Subsequent Event [Member]	Mar. 31, 2013 Term Loan A [Member] 2012-1 Term Loan A [Member]	Mar. 31, 2013 Term Loan A [Member] 2012-1 Term Loan A [Member] Minimum [Member] BasisPoint	Mar. 31, 2013 Term Loan A [Member] 2012-1 Term Loan A [Member] Maximum [Member] BasisPoint
Line of Credit Facility [Line Items]
Debt instrument, face amount	$ 5,430,247,000		$ 5,440,073,000							$ 500,000,000		$ 200,000,000
Eurodollar Rate margin				0.01875	0.02375					275			200	250
Base rate margin				0.00875	0.01375					175			100	150
Base rate floor										2.00%
Eurodollar rate floor										1.00%
Accrued interest on Term Loan										3.75%		2.46%
Repayments of long-term debt, quarterly						2,500,000	3,750,000	5,000,000		1,250,000
Financing fees									2,700,000	4,900,000
Percentage of par value price for issuance of term loan										99.75%
Repayment of debt	4,500,000	1,250,000							2,500,000	1,300,000
Term Loan, Principal balance									192,500,000	491,300,000
Term Loan, outstanding balance paid off											310,700,000
Wrote off of deferred financing fees											800,000
Wrote off of discount related to debt											$ 600,000