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Income Taxes (Details) |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Dec. 11, 2019 USD ($) | Dec. 31, 2019 USD ($) county | Dec. 31, 2018 USD ($) | Dec. 31, 2019 USD ($) county | Dec. 31, 2018 USD ($)
Income Tax Contingency [Line Items] |  |  |  |  |
Income tax expense (benefit) related to continuing operations |  | $ 47,000,000 | $ 123,000,000 | $ (111,000,000) | $ 245,000,000
Discrete tax benefit recognized |  | $ 21,000,000 |  | $ 21,000,000 |
Number of counties that filed claims | county |  | 2 |  | 2 |
Tax benefit on goodwill impairment |  |  |  |  | 0
Pretax goodwill impairment charges |  | $ 2,000,000 | $ 21,000,000 | $ 2,000,000 | $ 591,000,000
Unrecognized tax benefits |  | 977,000,000 |  | 977,000,000 |
Unrecognized tax benefits that would reduce income tax expense and the effective tax rate |  | 817,000,000 |  | 817,000,000 |
Possible decrease in unrecognized tax benefits during the next twelve months |  | 51,000,000 |  | 51,000,000 |
Planned divestiture in Medical-Surgical Solutions business |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Discrete tax benefit recognized |  | 24,000,000 |  | 24,000,000 |
Settlement with Taxing Authority [Member] |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Discrete tax benefit recognized |  | 20,000,000 |  |  |
Decrease in unrecognized tax benefits |  | 22,000,000 |  |  |
Settlement Agreement with State of California [Member] |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Discrete tax benefit recognized |  |  |  | 28,000,000 |
Decrease in unrecognized tax benefits |  |  |  | 91,000,000 |
Held-for-sale | German Wholesale Joint Venture |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Tax benefit recognized for impairment charge |  | 0 |  | 0 |
Impairment loss | $ 282,000,000 | $ 282,000,000 |  | $ 282,000,000 |

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