v3.21.2

Other Financial Data - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Jun. 30, 2021 | Sep. 30, 2020 | Jul. 01, 2021 | Dec. 31, 2020
Other Financial Data [Line Items] |  |  |  |  |  |
Allowance for expected credit losses | $ 4 |  |  |  | $ 0 | $ 15
Business combination, fixed assets acquired, accumulated depreciation | 0 |  |  |  |  |
Fixed assets, net | 219 |  |  |  |  | 334
Contract with customer, liability, revenue recognized | 22 |  | $ 101 | $ 152 |  |
Finance Leased Assets Included in Computer Equipment |  |  |  |  |  |
Other Financial Data [Line Items] |  |  |  |  |  |
Fixed assets, net | 67 |  |  |  |  | 83
Interest Rate Swaps |  |  |  |  |  |
Other Financial Data [Line Items] |  |  |  |  |  |
Derivative asset, noncurrent | 5 |  |  |  |  |
Derivative liability, current | 12 |  |  |  |  | 28
Derivative liability, noncurrent | 1 |  |  |  |  | $ 19
Cost of Services, Exclusive of Depreciation and Amortization |  |  |  |  |  |
Other Financial Data [Line Items] |  |  |  |  |  |
Amortization expense | $ 17 | $ 15 | $ 33 | $ 47 |  |

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