Other Income (Expense) - MEC (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Component of Other Income (Expense), Nonoperating [Line Items]
Other, net	$ (7)	$ (17)	$ 88
MEC
Component of Other Income (Expense), Nonoperating [Line Items]
Other, net	0	53	52
MEC | Non-service cost components of postretirement employee benefit plans
Component of Other Income (Expense), Nonoperating [Line Items]
Other, net	9	26	24
MEC | Corporate-owned life insurance (loss) income
Component of Other Income (Expense), Nonoperating [Line Items]
Other, net	(16)	21	16
MEC | Gains on disposition of assets
Component of Other Income (Expense), Nonoperating [Line Items]
Other, net	0	0	6
MEC | Interest income and other, net
Component of Other Income (Expense), Nonoperating [Line Items]
Other, net	$ 7	$ 6	$ 6