Healthcare Technology Net Asset Exchange - Summarized Financial Information (Details) - Change Healthcare, LLC (“Change Healthcare”) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Schedule of Equity Method Investments [Line Items]
Net Income (Loss)	$ 5	$ 59
Joint Venture
Schedule of Equity Method Investments [Line Items]
Revenues	856	865
Income (Loss) from Continuing Operations	7	(84)
Net Income (Loss)	$ 7	$ (84)

Amount of income (loss) from continuing operations reported by an equity method investee.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The amount of net income (loss) reported by an equity method investment of the entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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