v3.21.2

Fair Value Measurement - Summary of Changes in Deferred Contingent Consideration Liabilities (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
Fair Value Disclosures [Abstract] |  |  |  |
Beginning balance | $ 29 | $ 29 | $ 26 | $ 22
Acquisitions | 0 | 3 | 2 | 3
Accretion of contingent consideration | 0 | 0 | 1 | 0
Ending Balance | $ 29 | $ 25 | $ 29 | $ 25

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