Subsequent Event (Details) $ / shares in Units, $ in Billions		12 Months Ended
	Oct. 27, 2015 USD ($) $ / shares	Aug. 31, 2015 Store State
Subsequent Event [Line Items]
Business Acquisition, Date of Acquisition Agreement		Oct. 27, 2015
Number of stores | Store		4,561
Number of states | State		31
Bridge loan facility period		364 days
Subsequent Event [Member]
Subsequent Event [Line Items]
Amount of cash stockholders entitled to receive (in dollars per share) | $ / shares	$ 9.00
Total enterprise value	$ 17.2
Senior unsecured bridge facility	12.8
Additional Bridge Loan [Member]
Subsequent Event [Line Items]
Bridge loan facility period		90 days
Additional Bridge Loan [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Senior unsecured bridge facility	$ 3.0