v3.21.2

Other Financial Data - Summary of Components of Other Current Assets (Details) - USD ($) $ in Millions | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Other Financial Data [Abstract] |  |
Deferred project costs | $ 39 | $ 53
Prepaid expenses | 65 | 57
Commissions receivable | 35 | 32
Other | 33 | 21
Total | $ 172 | $ 163

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