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Income Taxes (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Dec. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Income tax expense related to continuing operations | $ 131 |  | $ 204 | $ 570 | $ 704
Net discrete tax benefits | 12 |  | 16 | 69 | 45
Goodwill impairment charge | $ 0 |  | 0 | 290 | 0
Non-deductible goodwill impairment charge |  |  |  | 269 |
Tax benefit of non-cash pre-tax impairment charge |  |  |  | $ 8 |
Net discrete tax benefits |  |  | $ 19 |  | $ (25)
Income tax rate (as a percent) | 16.80% |  | 24.10% | 25.70% | 27.30%
Unrecognized tax benefits | $ 437 |  |  | $ 437 |
Unrecognized tax benefits that would reduce income tax expense and the effective tax rate | 296 |  |  | 296 |
Income tax (benefit) expense | 3 |  | $ 3 | (9) | $ 9
Accrued interest and penalties on unrecognized tax benefits | $ 43 |  | $ 78 | 43 | $ 78
Technology Solutions |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Goodwill impairment charge |  | $ 290 |  | 290 |
After-tax goodwill impairment |  | $ 282 |  | 282 |
Adoption of amended accounting guidance |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Tax benefit recognized related to excess tax benefits arising from adoption of ASU 2016-09 |  |  |  | $ (47) |

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