Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified		1 Months Ended		18 Months Ended	1 Months Ended	6 Months Ended
	Jul. 28, 2012	Apr. 30, 2012 Consumer Class Action Claims Pricing and Promotion Maximum	Jun. 30, 2012 Consumer Class Action Claims Website Tracking and Coding Maximum	Jul. 28, 2012 Consumer Class Action Claims Zip Code Claims item	May 31, 2011 Consumer Class Action Claims Payment Card Terminal Tampering item	Jul. 28, 2012 Consumer Class Action Claims Payment Card Terminal Tampering item	May 03, 2011 Consumer Class Action Claims Payment Card Terminal Tampering item
Commitments and Contingencies
Damages, penalties and fees sought by plaintiff		$ 5	$ 5
Additional purported class action lawsuits				3	2	4
Number of payment card terminals tampered							90
Number of payment card terminals removed and replaced						7,100
Aggregate estimate of possible loss	$ 17