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Income Taxes - Narrative (Details) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Oct. 31, 2022 | Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Income Tax Contingency [Line Items] |  |  |  |  |
Effective income tax rate reconciliation, tax (benefit), share-based payment arrangement, amount |  |  |  | $ (53) |
Discrete tax benefit recognized due to GILTI |  |  | $ 55 |  |
Discrete tax benefit recognized due to statute of limitation expirations |  |  |  |  | $ 97
Loss (gain) to remeasure disposal group to fair value |  |  |  | (35) | 470
Unrecognized tax benefits |  | $ 1,500 |  | 1,500 |
Unrecognized tax benefits that would impact effective tax rate |  | 1,300 |  | $ 1,300 |
Effective income tax rate reconciliations, tax credit, amount |  | $ 16 |  |  |
Tax Receivable Agreement (“TRA”) |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Percentage of net cash tax savings realized or deemed realized under TRA (percent) |  | 85.00% |  | 85.00% |
Tax Receivable Agreement (“TRA”) | Subsequent Event |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Gain on early contract termination | $ 126 |  |  |  |
Held-for-sale | E.U. Businesses (Disposal Group) |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Loss (gain) to remeasure disposal group to fair value |  | $ (23) | $ 491 | $ (35) | $ 491
Minimum |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Possible decrease in unrecognized tax benefits during the next twelve months |  | 150 |  | 150 |
Maximum |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Possible decrease in unrecognized tax benefits during the next twelve months |  | $ 180 |  | $ 180 |

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- Definition Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(3) -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319 + Details
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- Definition Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 740 -Section 35 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=126970579&loc=d3e23163-113944 + Details
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