Retirement Plans (Amounts Recognized on The Consolidated Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Current liabilities	$ (288)	$ (306)
Noncurrent liabilities	(2,813)	(5,182)
Pension Benefits
Noncurrent assets	134	69
Current liabilities	(176)	(181)
Noncurrent liabilities	(2,570)	(4,829)
Net liability recognized	(2,612)	(4,941)
Other  Post-retirement Benefits
Noncurrent assets	292	121
Current liabilities	(112)	(125)
Noncurrent liabilities	(243)	(353)
Net liability recognized	$ (63)	$ (357)