Leases - Summary of Lease Cost (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Lease Cost [Abstract]
Operating lease cost		$ 136	$ 121
Finance lease cost
Amortization of leased assets		1	1
Variable lease cost	[1]	95	49
Short-term lease cost		2	3
Sub-lease income		(8)	(6)
Total lease cost		$ 226	$ 168

[1] In the first quarter of 2021 and 2020, the Company was granted $5 million and $14 million, respectively, in lease concessions from landlords related to the effects of the COVID-19 pandemic. The lease concessions were primarily in the form of rent reduction over the period of time when the Company’s restaurant business was adversely impacted. The Company applied the interpretive guidance in a FASB staff Q&A document issued in April 2020 and elected: (1) not to evaluate whether a concession received in response to the COVID-19 pandemic is a lease modification and (2) to assume such concession was contemplated as part of the existing lease contract with no contract modification. Such concession was recognized as negative variable lease cost in the period the concession was granted.