Fair Value Measurements and Derivative Instruments (Recurring) (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions		Dec. 31, 2023	Dec. 31, 2022
Total Fair Value
Assets:
Derivative financial instruments	[1]	$ 144	$ 204
Total Assets		144	204
Liabilities:
Derivative financial instruments	[1]	66	136
Total Liabilities		66	136
Level 1
Assets:
Derivative financial instruments	[1],[2]	0	0
Total Assets	[2]	0	0
Liabilities:
Derivative financial instruments	[1],[2]	0	0
Total Liabilities	[2]	0	0
Level 2
Assets:
Derivative financial instruments	[1],[3]	144	204
Total Assets	[3]	144	204
Liabilities:
Derivative financial instruments	[1],[3]	66	136
Total Liabilities	[3]	66	136
Level 3
Assets:
Derivative financial instruments	[1],[4]	0	0
Total Assets	[4]	0	0
Liabilities:
Derivative financial instruments	[1],[4]	0	0
Total Liabilities	[4]	$ 0	$ 0

[1] Consists of foreign currency forward contracts, interest rate and fuel swaps. Refer to the "Fair Value of Derivative Instruments" table for breakdown by instrument type.

[2] Inputs based on quoted prices (unadjusted) in active markets for identical assets or liabilities that we have the ability to access. Valuation of these items does not entail a significant amount of judgment. No Level 1 inputs were used in fair value measurements of other financial instruments as of December 31, 2023 and 2022.

[3] Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. For foreign currency forward contracts, interest rate swaps and fuel swaps, fair value is derived using valuation models that utilize the income valuation approach. These valuation models take into account the contract terms, such as maturity as well as other inputs, such as foreign exchange rates and curves, fuel types, fuel curves and interest rate yield curves. Derivative instrument fair values take into account the creditworthiness of the counterparty and the Company.

[4] Inputs that are unobservable. No Level 3 inputs were used in fair value measurements of other financial instruments as of December 31, 2023 and 2022