Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net earnings	$ 440	$ 400	$ 2,023	$ 911
Other comprehensive income (loss), net of tax:
Cumulative translation adjustments	(1)	(8)	2	(14)
Amortization of net actuarial loss	13	15	27	30
Total other comprehensive income, net of tax	12	7	29	16
Total comprehensive income	$ 452	$ 407	$ 2,052	$ 927