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Amount of direct costs of the business combination including legal, accounting, and other costs incurred during the period to consummate the business acquisition.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Acquisitions 2 (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
Acquisitions 2 (Details) - USD ($) $ in Millions	Sep. 30, 2016	Jun. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Mar. 31, 2016	Jul. 08, 2015
Business Combinations [Abstract]
Accrued acquisition-related costs related to purchase price amounts withheld to support indemnification obligations	$ 3			$ 3		$ 3
Business Acquisition
Total revenue	1,018		$ 1,005	2,017	$ 1,982
Net income (loss)	$ 212		174	$ 410	386
Rally
Business Acquisition
Percentage of outstanding shares of Rally common stock acquired							100.00%
Purchase price for Rally		$ 519					$ 519
Fiscal Year 2016 Acquisitions \| General and Administrative
Business Acquisition
Transaction costs			$ 17		$ 20
Rally and Xceedium
Business Acquisition
Total revenue		35
Net income (loss)		$ (5)