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Investments and Variable Interest Entities - Narrative (Details) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended | 21 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2025 USD ($) | Jun. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2023 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2023 USD ($) | Jun. 30, 2025 USD ($) | May 31, 2025 | Dec. 31, 2024 USD ($)
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |
Unrealized gains (losses) recognized | $ (55) |  | $ (15) |  | $ (85) | $ (117) |  |  |  |
Cash distribution received from equity method investments |  |  |  |  | 113 | 244 |  |  |  |
Other investments | 190 |  |  |  | 190 |  |  |  |  | $ 184
Total carrying value of debt | 99,100 |  |  |  | 99,100 |  |  |  |  | 99,100
Consolidated variable interest entity's assets included in condensed consolidated balance sheet | 272,995 |  |  |  | 272,995 |  |  |  |  | 266,211
Short-Term Instruments |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |
Other investments | $ 0 |  |  |  | 0 |  |  |  |  | 0
Other Investments |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |
Proceeds from short-term instruments |  |  |  |  | $ 0 | 632 |  |  |  |
Purchase of short-term instruments |  |  |  |  |  | 443 |  |  |  |
Variable Interest Entity, Primary Beneficiary | Universal Beijing Resort |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |
Ownership percentage in variable interest entity | 30.00% |  |  |  | 30.00% |  |  |  |  |
Total carrying value of debt | $ 3,500 |  |  |  | $ 3,500 |  |  |  |  | 3,400
Consolidated variable interest entity's assets included in condensed consolidated balance sheet | 7,400 |  |  |  | 7,400 |  |  |  |  | 7,300
Consolidated variable interest entity's liabilities included in condensed consolidated balance sheet | 7,200 |  |  |  | 7,200 |  |  |  |  | 7,000
Variable Interest Entity, Primary Beneficiary | Universal Beijing Resort | Universal Beijing Resort Term Loans |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |
Total carrying value of debt | 3,100 |  |  |  | 3,100 |  |  |  |  | 3,000
Atairos |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |
Cash capital contributions for equity method investments |  |  |  |  | 117 | $ 60 |  |  |  |
Equity method investments and certain retained distributions | 5,000 |  |  |  | 5,000 |  |  |  |  | $ 5,100
Atairos | Variable Interest Entity, Not Primary Beneficiary |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |
Remaining unfunded capital commitment | $ 1,300 |  |  |  | $ 1,300 |  |  |  |  |
Hulu |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |
Equity method investment, ownership percentage | 0.00% |  |  |  | 0.00% |  |  |  | 33.00% |
Proceeds from sale of equity method investments |  | $ 439 |  | $ 9,200 |  |  |  | $ 9,600 |  |
Equity method investments, prior capital calls paid |  |  |  |  |  |  | $ 557 |  |  |
Cash receivable related to receive portion of estimated future tax benefits from equity investment |  | $ 792 |  |  |  |  |  |  |  |
Right to receive share of estimated future tax benefits from sale of equity method investment (as a percent) |  | 0.50 |  |  |  |  |  | 0.50 |  |
Pre-tax gain from sale of investment |  | $ 9,400 |  |  |  |  |  |  |  |

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