Subsequent Events (Details) (Sale [Member], USD $) In Millions, unless otherwise specified	Feb. 03, 2012 Day Y
Sale [Member]
Subsequent Event [Line Items]
Business Disposal, Cash Received for Assets	$ 100
Period after Business Disposal where Purchaser May Procure Certain Hardware, Software and Services	5
Business Disposal, Software and Services Margin Threshold Triggering Additional Payment	25
Business Combination, Maximum Closing Date Margin Following Regulatory Approval	3
Business Combination, Break Up Fee to be Received if Transaction is Terminated	10
Carrying Value of Assets In Disposal Group	$ 54