Other Comprehensive Income / (Loss) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Comprehensive earnings		$ 3,317	$ 3,134	$ 5,625
Other Comprehensive Income (Loss):
Reclassification of Stranded Tax Effects			(107)
Income Before Reclassifications		(48)	(119)	161
Amounts Reclassified to Net Earnings		31	32	58
Tax (Expense) Benefit		3	19	(65)
Total Other Comprehensive (Loss) Income		(14)	(175)	154
Pension and Other Post-Employment Benefits
Other Comprehensive Income (Loss):
Beginning Balance		(604)	(440)	(580)
Reclassification of Stranded Tax Effects			(108)
Income Before Reclassifications		(43)	(111)	148
Amounts Reclassified to Net Earnings		23	38	56
Tax (Expense) Benefit		5	17	(64)
Total Other Comprehensive (Loss) Income		(15)	(164)	140
Ending Balance		(619)	(604)	(440)
Other
Other Comprehensive Income (Loss):
Beginning Balance		(57)	(46)	(60)
Reclassification of Stranded Tax Effects			1
Income Before Reclassifications		(5)	(8)	13
Amounts Reclassified to Net Earnings		8	(6)	2
Tax (Expense) Benefit		(2)	2	(1)
Total Other Comprehensive (Loss) Income		1	(11)	14
Ending Balance		(56)	(57)	(46)
Accumulated Other Comprehensive Income (Loss)
Other Comprehensive Income (Loss):
Beginning Balance		(661)	(486)	(640)
Total Other Comprehensive (Loss) Income	[1]	(14)	(175)	154
Ending Balance		$ (675)	$ (661)	$ (486)

[1] Accumulated Other Comprehensive Loss year-end balances shown above are net of tax. The associated taxes were $184 million, $180 million and $162 million for 2019, 2018 and 2017, respectively. For additional information see Note 16, Other Comprehensive Income.