Debt - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended	6 Months Ended			6 Months Ended				1 Months Ended			6 Months Ended		1 Months Ended			6 Months Ended
	Apr. 30, 2014	Jun. 30, 2014	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Jun. 30, 2014 2013 Senior Secured Credit Facility	Dec. 31, 2013 2013 Senior Secured Credit Facility	Jun. 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 Eurodollar Rate Plus	Jul. 31, 2013 2013 Term Loan Facility	Jun. 30, 2014 2013 Term Loan Facility	Jun. 30, 2014 2013 Revolving Loan Facility	Jun. 30, 2013 2013 Revolving Loan Facility	Jul. 31, 2013 LIBOR	Jul. 31, 2013 ABR	Jul. 31, 2013 Federal Funds Rate Plus	Jun. 30, 2014 2013 Credit Facility	Jun. 30, 2013 2013 Credit Facility
Debt Instrument [Line Items]
Credit facility, borrowing capacity		$ 15,000,000	$ 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.
Interest rate										1.00%						2.00%	0.50%
Applicable margin										2.00%					3.00%
Loss on early extinguishment of debt		178,000	178,000	134,000														178,000	134,000
Excess cash flow payment	14,627,000
Excess cash flow prepayment			8,725,000
Principal payments are due on quarterly			538,000			538,000
Debt Instrument, Maturity Date			Jul. 31, 2020			Jul. 31, 2020
Principal excess cash flow prepayments				8,000,000
Credit Facility		212,721,000	212,721,000		228,404,000	227,842,000	228,404,000
Credit Facility, fair value								212,577,000	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