Employee Benefit Plans - Fair Value of Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension and Other Postretirement Plans
Liabilities	$ (17)	$ (19)
Other payables
Pension and Other Postretirement Plans
Liabilities	(17)	(19)
Level 1
Pension and Other Postretirement Plans
Liabilities	0	0
Level 1 | Other payables
Pension and Other Postretirement Plans
Liabilities	0	0
Level 2
Pension and Other Postretirement Plans
Liabilities	(17)	(19)
Level 2 | Other payables
Pension and Other Postretirement Plans
Liabilities	(17)	(19)
Level 3
Pension and Other Postretirement Plans
Liabilities	0	0
Level 3 | Other payables
Pension and Other Postretirement Plans
Liabilities	0	0
Pension Plans
Pension and Other Postretirement Plans
Fair value of plan assets	3,605	3,985	$ 3,553
Liabilities	(593)	(632)
Pension Plans | Assets
Pension and Other Postretirement Plans
Fair value of plan assets	3,153	3,483
Pension Plans | Cash and cash equivalents
Pension and Other Postretirement Plans
Fair value of plan assets	9	4
Pension Plans | U.S. government and agency securities
Pension and Other Postretirement Plans
Fair value of plan assets	3,073	3,359
Pension Plans | Corporate and other debt—CDO
Pension and Other Postretirement Plans
Fair value of plan assets	1	4
Pension Plans | Derivative contracts
Pension and Other Postretirement Plans
Fair value of plan assets	3	2
Pension Plans | Other investments
Pension and Other Postretirement Plans
Fair value of plan assets	65	61
Pension Plans | Other receivables
Pension and Other Postretirement Plans
Fair value of plan assets	2	53
Pension Plans | Level 1 | Assets
Pension and Other Postretirement Plans
Fair value of plan assets	2,768	3,042
Pension Plans | Level 1 | Cash and cash equivalents
Pension and Other Postretirement Plans
Fair value of plan assets	9	4
Pension Plans | Level 1 | U.S. government and agency securities
Pension and Other Postretirement Plans
Fair value of plan assets	2,759	3,038
Pension Plans | Level 1 | Corporate and other debt—CDO
Pension and Other Postretirement Plans
Fair value of plan assets	0	0
Pension Plans | Level 1 | Derivative contracts
Pension and Other Postretirement Plans
Fair value of plan assets	0	0
Pension Plans | Level 1 | Other investments
Pension and Other Postretirement Plans
Fair value of plan assets	0	0
Pension Plans | Level 1 | Other receivables
Pension and Other Postretirement Plans
Fair value of plan assets	0	0
Pension Plans | Level 2 | Assets
Pension and Other Postretirement Plans
Fair value of plan assets	320	380
Pension Plans | Level 2 | Cash and cash equivalents
Pension and Other Postretirement Plans
Fair value of plan assets	0	0
Pension Plans | Level 2 | U.S. government and agency securities
Pension and Other Postretirement Plans
Fair value of plan assets	314	321
Pension Plans | Level 2 | Corporate and other debt—CDO
Pension and Other Postretirement Plans
Fair value of plan assets	1	4
Pension Plans | Level 2 | Derivative contracts
Pension and Other Postretirement Plans
Fair value of plan assets	3	2
Pension Plans | Level 2 | Other investments
Pension and Other Postretirement Plans
Fair value of plan assets	0	0
Pension Plans | Level 2 | Other receivables
Pension and Other Postretirement Plans
Fair value of plan assets	2	53
Pension Plans | Level 3
Pension and Other Postretirement Plans
Fair value of plan assets	65	61	$ 53
Pension Plans | Level 3 | Assets
Pension and Other Postretirement Plans
Fair value of plan assets	65	61
Pension Plans | Level 3 | Cash and cash equivalents
Pension and Other Postretirement Plans
Fair value of plan assets	0	0
Pension Plans | Level 3 | U.S. government and agency securities
Pension and Other Postretirement Plans
Fair value of plan assets	0	0
Pension Plans | Level 3 | Corporate and other debt—CDO
Pension and Other Postretirement Plans
Fair value of plan assets	0	0
Pension Plans | Level 3 | Derivative contracts
Pension and Other Postretirement Plans
Fair value of plan assets	0	0
Pension Plans | Level 3 | Other investments
Pension and Other Postretirement Plans
Fair value of plan assets	65	61
Pension Plans | Level 3 | Other receivables
Pension and Other Postretirement Plans
Fair value of plan assets	0	0
Pension Plans | Measured at NAV
Pension and Other Postretirement Plans
Fair value of plan assets	469	521
Pension Plans | Measured at NAV | Commingled Trust Funds: Money Market
Pension and Other Postretirement Plans
Fair value of plan assets	33	48
Pension Plans | Measured at NAV | Foreign Funds: Fixed Income
Pension and Other Postretirement Plans
Fair value of plan assets	162	169
Pension Plans | Measured at NAV | Foreign Funds: Liquidity
Pension and Other Postretirement Plans
Fair value of plan assets	39	54
Pension Plans | Measured at NAV | Foreign Funds: Targeted Cash Flow
Pension and Other Postretirement Plans
Fair value of plan assets	$ 235	$ 250