Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) $ in Millions		Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Contingent consideration [Member] | Fair Value Inputs, Discount Rate [Member]
Liabilities:
Fair value inputs, weighted-average discount rate		0.1199	0.1192
Contingent consideration [Member] | Fair Value Inputs, Discount Rate [Member] | Minimum [Member]
Liabilities:
Fair value inputs, weighted-average discount rate		0.0353
Contingent consideration [Member] | Fair Value Inputs, Discount Rate [Member] | Maximum [Member]
Liabilities:
Fair value inputs, weighted-average discount rate		0.1380
Recurring [Member]
Assets:
Mutual funds / exchange traded funds		$ 6	$ 9
Derivative financial instruments	[1]	3	18
Liabilities:
Contingent consideration	[2]	54	51
Derivative financial instruments	[1]	27	0
Recurring [Member] | Certificates of Deposit And Term Deposits [Member]
Assets:
Mutual funds / exchange traded funds			200
Recurring [Member] | Fiduciary Assets [Member]
Assets:
Mutual funds / exchange traded funds		128	152
Recurring [Member] | Level 1 [Member]
Assets:
Mutual funds / exchange traded funds		6	9
Derivative financial instruments	[1]	0	0
Liabilities:
Contingent consideration	[2]	0	0
Derivative financial instruments	[1]	0	0
Recurring [Member] | Level 1 [Member] | Certificates of Deposit And Term Deposits [Member]
Assets:
Mutual funds / exchange traded funds			200
Recurring [Member] | Level 1 [Member] | Fiduciary Assets [Member]
Assets:
Mutual funds / exchange traded funds		128	152
Recurring [Member] | Level 2 [Member]
Assets:
Mutual funds / exchange traded funds		0	0
Derivative financial instruments	[1]	3	18
Liabilities:
Contingent consideration	[2]	0	0
Derivative financial instruments	[1]	27	0
Recurring [Member] | Level 2 [Member] | Certificates of Deposit And Term Deposits [Member]
Assets:
Mutual funds / exchange traded funds			0
Recurring [Member] | Level 2 [Member] | Fiduciary Assets [Member]
Assets:
Mutual funds / exchange traded funds		0	0
Recurring [Member] | Level 3 [Member]
Assets:
Mutual funds / exchange traded funds		0	0
Derivative financial instruments	[1]	0	0
Liabilities:
Contingent consideration	[2]	54	51
Derivative financial instruments	[1]	0	0
Recurring [Member] | Level 3 [Member] | Certificates of Deposit And Term Deposits [Member]
Assets:
Mutual funds / exchange traded funds			0
Recurring [Member] | Level 3 [Member] | Fiduciary Assets [Member]
Assets:
Mutual funds / exchange traded funds		$ 0	$ 0

[1] See Note 9 — Derivative Financial Instruments for further information on our derivative investments.

[2] Probability weightings are based on our knowledge of the past and planned performance of the acquired entity to which the contingent consideration applies. The fair value weighted-average discount rates used in our material contingent consideration calculations were 11.99% and 11.92% at September 30, 2022 and December 31, 2021, respectively. The range of these discount rates was 3.53% - 13.80% at September 30, 2022. Using different probability weightings and discount rates could result in an increase or decrease of the contingent consideration payable.