Intangible Assets and Goodwill - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended
	Oct. 02, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment	$ 0	$ 0	$ 0	$ 0
Franchise asset impairment charge		2,200,000	600,000	0
Definite lived intangible assets, amortization expense		$ 1,200,000	$ 1,600,000	$ 1,600,000
Lease Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period		17 years