Subsequent Event - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended	0 Months Ended
	Dec. 31, 2013	Feb. 01, 2014 Subsequent Event [Member] State Location
Subsequent Event [Line Items]
Acquisition price paid in cash	$ 26,920	$ 60,000
Number of locations in which the company will add following the close of the acquisition		33
Number of states in which the company will add following the close of the acquisition		5
Expected closing date of acquisition		Mar. 31, 2014