Divestitures 2 (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	3 Months Ended
Dec. 31, 2014	Sep. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill written off related to sale of discontinued component	$ 109
Arcserve [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of discontinued component		170
Gain on disposal of discontinued component, net of tax		19
Tax expense related to gain on disposal of discontinued component		77
Goodwill written off related to sale of discontinued component		$ 109

Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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Amount of tax expense or benefit on gain (loss), not previously recognized, resulting from the sale of a business component.

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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