Fair Value Measurements - Assets and Liabilities at Fair Value, Recurring (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Not Designated
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Derivatives - not designated	$ 122	$ 74
Derivatives - not designated	230	173
Designated
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Derivatives - not designated	2
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Total Assets at Fair Value	15
Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Marketable Securities	34	31
Total Assets at Fair Value	156	105
Total Liabilities at Fair Value	231	173
Recurring Basis | Not Designated
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Derivatives - not designated	122	74
Derivatives - not designated	229	173
Recurring Basis | Designated
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Derivatives - not designated	2	0
Recurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Marketable Securities	34	31
Total Assets at Fair Value	138	68
Total Liabilities at Fair Value	59	58
Recurring Basis | Level 1 | Not Designated
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Derivatives - not designated	104	37
Derivatives - not designated	57	58
Recurring Basis | Level 1 | Designated
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Derivatives - not designated	2	0
Recurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Marketable Securities	0	0
Total Assets at Fair Value	18	37
Total Liabilities at Fair Value	172	115
Recurring Basis | Level 2 | Not Designated
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Derivatives - not designated	18	37
Derivatives - not designated	172	115
Recurring Basis | Level 2 | Designated
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Derivatives - not designated	0	0
Recurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Marketable Securities	0	0
Total Assets at Fair Value	0	0
Total Liabilities at Fair Value	0	0
Recurring Basis | Level 3 | Not Designated
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Derivatives - not designated	0	0
Derivatives - not designated	0	0
Recurring Basis | Level 3 | Designated
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Derivatives - not designated	$ 0	$ 0