Long-Term Debt - 2013 Credit Facility - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended			0 Months Ended
	Dec. 31, 2011	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 30, 2014	Dec. 31, 2013	May 31, 2013	Aug. 02, 2013
Debt Instrument [Line Items]
Senior Secured debt							$ 405,000,000
Maturity date of revolving credit facility		May 31, 2013
Principal amount repurchased	16,200,000
Gain (loss) on debt extinguishment	(400,000)	(246,000)	(29,675,000)	(3,743,000)
2013 Credit Facility
Debt Instrument [Line Items]
Additional borrowing capacity							100,000,000
Effective interest rate			3.50%			3.50%
Interest rate on borrowings under 2013 Credit Facility		if a Base Rate Loan, one and one half percent (1.50%) per annum and (B) if a LIBOR Rate Loan, two and one half percent (2.50%) per annum
Percentage of repricing fee		1.00%
Certain customary events of default, number of business days to default in the payment of interest on borrowings		3 days
Certain customary events of default, number of days default continue for compliance with other agreement		30 days
Certain customary events of default, number of days default continue for financial statement delivery obligations		10 days
Certain customary events of default ,indebtedness aggregate amount		15,000,000
Certain customary events of default ,failure in payment of final judgments aggregate amount		15,000,000
Certain customary events of default ,failure in payment of final judgments aggregate amount period		30 days
2013 Credit Facility | Base Rate Margin
Debt Instrument [Line Items]
Variable interest rate basis spread on debt		1.50%
2013 Credit Facility | LIBOR Margin
Debt Instrument [Line Items]
Variable interest rate basis spread on debt		2.50%
Term Loan A | 2013 Credit Facility
Debt Instrument [Line Items]
Senior Secured debt							20,000,000
Maturity date of revolving credit facility		Aug. 01, 2013
Term Loan B Facility | 2013 Credit Facility
Debt Instrument [Line Items]
Senior Secured debt							375,000,000
Maturity date of revolving credit facility		May 31, 2020
Senior Secured Revolving Credit Facility | 2013 Credit Facility
Debt Instrument [Line Items]
Senior Secured debt							30,000,000
Maturity date of revolving credit facility		May 31, 2018
Term loan facility
Debt Instrument [Line Items]
Interest rate on borrowings under 2013 Credit Facility		if a Base Rate Loan, one and one half percent (1.50%) per annum and (ii) if a LIBOR Rate Loan, two and one half percent (2.50%) per annum;
Term loan facility | Base Rate Margin
Debt Instrument [Line Items]
Variable interest rate basis spread on debt		1.50%
Term loan facility | LIBOR Margin
Debt Instrument [Line Items]
Variable interest rate basis spread on debt		2.50%
Term Loan B
Debt Instrument [Line Items]
Principal amount repurchased								324,000,000
Gain (loss) on debt extinguishment		29,700,000
Repayment of loans					20,000,000	10,000,000
Term Loan B | 2013 Credit Facility
Debt Instrument [Line Items]
Period considered for applicability of repricing fees		6 months
Redemption price on principal amount with net proceeds, accrued and unpaid expense								106.563%
Carrying value of term loan		340,300,000
Estimated fair value of term loan		$ 340,300,000