Assets Held for Sale - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended		3 Months Ended	1 Months Ended				1 Months Ended		1 Months Ended
	Nov. 30, 2012	Dec. 31, 2012 Location	Sep. 30, 2012	Dec. 31, 2012 March 31, 2013	Nov. 30, 2012 PFGI II LLC Note	Jan. 25, 2013 Subsequent Event PFGI II LLC Note	Sep. 30, 2012 Firestone Colorado	Dec. 31, 2012 Wheat Ridge Colorado Location	Jan. 25, 2013 Wheat Ridge Colorado Subsequent Event	Dec. 31, 2012 Thornton Colorado Location	Jan. 25, 2013 Thornton Colorado Subsequent Event March 31, 2013
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale		$ 1,888,000	$ 1,380,000				$ 1,380,000
Net proceeds from sale leaseback transaction	1,377,000	1,377,000		1,085,000					870,000		1,085,000
Repayment of notes payable					$ 765,000	$ 531,000
Number of site		2						1		1