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Stock-Based Compensation - Compensation Expense (Details) - Executives - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
SGI Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
SGI awards	$ 58		$ 58		$ 73
SGI Awards \| General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based liabilities paid	10	$ 3	20	$ 34
Performance based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
SGI awards	15		15		$ 8
Performance based awards \| General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based liabilities paid	$ 2	$ 1	$ 14	$ 5