Consolidated Statements of Operations and Comprehensive Income (Loss) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Sales and service revenues
Product sales	$ 5,573	$ 5,631	$ 5,665
Service revenues	1,868	1,437	1,355
Total sales and service revenues	7,441	7,068	7,020
Cost of sales and service revenues
Cost of product sales	4,444	4,380	4,319
Cost of service revenues	1,574	1,228	1,198
Income (loss) from operating investments, net	12	6	10
Other income and gains		15
General and administrative expenses	570	623	669
Goodwill Impairment			75
Operating income (loss)	865	858	769
Other income (expense)
Interest expense	(94)	(74)	(137)
Other, net	1
Earnings (loss) before income taxes	772	784	632
Federal and foreign income taxes	293	211	228
Net earnings (loss)	$ 479	$ 573	$ 404
Basic earnings (loss) per share	$ 10.48	$ 12.24	$ 8.43
Weighted-average common shares outstanding (in shares)	45.7	46.8	47.9
Diluted earnings (loss) per share	$ 10.46	$ 12.14	$ 8.36
Weighted-average diluted shares outstanding (in shares)	45.8	47.2	48.3
Other comprehensive income (loss)
Change in unamortized benefit plan costs	$ 59	$ (172)	$ 34
Other	14	(1)	(5)
Tax benefit (expense) for items of other comprehensive income	(22)	67	(12)
Other comprehensive income (loss), net of tax	51	(106)	17
Comprehensive income (loss)	$ 530	$ 467	$ 421