Divestitures 2 (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended	3 Months Ended
Mar. 31, 2015	Sep. 30, 2014
Additional Disclosures by Disposal Groups, Including Discontinued Operations
Goodwill written off related to sale of discontinued component	$ 109
Arcserve
Additional Disclosures by Disposal Groups, Including Discontinued Operations
Proceeds from sale of discontinued component		170
Gain on disposal of discontinued component, net of tax		20
Tax expense related to gain on disposal of discontinued component		77
Goodwill written off related to sale of discontinued component		$ 109

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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