Debt - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended	9 Months Ended		12 Months Ended				0 Months Ended			0 Months Ended			9 Months Ended			9 Months Ended		12 Months Ended
	Apr. 09, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	May 31, 2014	Sep. 30, 2014 Fair Value, Inputs, Level 2 2013 Senior Secured Credit Facility	Dec. 31, 2013 Fair Value, Inputs, Level 2 2013 Senior Secured Credit Facility	Jul. 31, 2013 London Interbank Offered Rate (LIBOR)	Jul. 31, 2013 London Interbank Offered Rate (LIBOR) Minimum	Jul. 31, 2013 Alternative Base Rate Minimum	Jul. 31, 2013 Federal Funds Effective Swap Rate	Jul. 31, 2013 Eurodollar	Jul. 31, 2013 Eurodollar Maximum	Sep. 30, 2014 2013 Term Loan Facility	Sep. 30, 2014 2013 Revolving Loan Facility	Sep. 30, 2013 2013 Revolving Loan Facility	Sep. 30, 2014 2013 Credit Facility	Sep. 30, 2013 2013 Credit Facility	Dec. 31, 2013 2013 Credit Facility
Debt Instrument [Line Items]
Credit facility, borrowing capacity						$ 15,000,000									$ 230,000,000	$ 10,000,000
Interest rate terms															Interest rates with respect to the term loan facility and revolving loan facility are based, at the Company’s option, on (a) adjusted London Interbank Offered Rate (“LIBOR”), provided that LIBOR shall be no less than 1% plus a maximum applicable margin of 3% or (b) Alternate Base Rate (“ABR”), provided that ABR shall be no less than 2%, which is equal to the greater of (1) JPMorgan Chase Bank, N.A.’s prime rate; (2) the Federal Funds Effective Rate plus 0.5% or (3) calculated Eurodollar Rate plus 1%, plus a maximum applicable margin of 2%. The applicable margin is subject to quarterly adjustments beginning in the first quarter of 2014 based on the Company’s total leverage ratio as defined in the 2013 Senior Secured Credit Facility.
Debt Instrument, Basis Spread on Variable Rate									3.00%			0.50%	1.00%	2.00%
Applicable margin										1.00%	2.00%
Loss on early extinguishment of debt		1,664,000	178,000	1,798,000	1,664,000													178,000	134,000
Debt Instrument, unamortized discount																				3,219,000
Debt issuance costs, net																				1,301,000
Debt Instrument, expense incurred																				1,918,000
Excess cash flow payment	14,627,000		6,416,000	8,000,000
Principal payments are due on quarterly			538,000
Debt Instrument, Maturity Date			Jul. 31, 2020
Credit Facility			212,197,000		228,404,000
Credit Facility, fair value							211,243,000	229,422,000
Revolving loan facility commitment fee on average daily amount of unused portion																0.50%
Outstanding balance of line of credit																0	0
Line of Credit Facility, Remaining Borrowing Capacity																$ 10,000,000