Supplemental Disclosures of Cash Flow Information and Non-Cash Financing and Investing Activities - Schedule of Reconciliation of Cash and Cash Equivalents and Restricted Cash Inclusive of Fiduciary Cash (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Dec. 31, 2023
Supplemental Cash Flow Elements [Abstract]
Cash and cash equivalents	$ 1,190	$ 675	$ 957
Fiduciary cash	2,271		1,744
Restricted cash	263
Total cash, cash equivalents and restricted cash inclusive of fiduciary cash at the end of the period	$ 3,724	$ 2,502	$ 2,701	$ 2,303