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Stock-Based Compensation - Compensation Expense (Details) - Executives - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
SGI Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Liabilities associated with SGI awards	$ 48		$ 92
SGI Awards \| Corporate General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	7	$ 10
Performance-Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Liabilities associated with SGI awards	16		$ 15
Performance-Based Awards \| Corporate General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 7	$ 15