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Income Taxes (Details) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Segment Reporting Information [Line Items] |  |  |  |
Income tax expense (benefit) related to continuing operations | $ (294,000,000) | $ 35,000,000 | $ (158,000,000) | $ 122,000,000
Tax benefit recognized resulting from goodwill impairment |  |  |  | 0
Pretax goodwill impairment charges | 0 | 0 | 0 | 570,000,000
Discrete tax benefit recognized | 28,000,000 | $ 42,000,000 |  |
Unrecognized tax benefits | 985,000,000 |  | 985,000,000 |
Unrecognized tax benefits that would reduce income tax expense and the effective tax rate | 812,000,000 |  | 812,000,000 |
Decrease in unrecognized tax benefits | 91,000,000 |  |  |
Possible decrease in unrecognized tax benefits during the next twelve months | $ 60,000,000 |  | $ 60,000,000 |
European Pharmaceutical Solutions |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax goodwill impairment charges |  |  |  | $ 570,000,000

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