Basis of Presentation (Unaudited) (Details 2) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Change in Accounting Estimate [Line Items]
Operating Income (Loss)	$ 797	$ 813	$ 1,536	$ 1,593
Net earnings	$ 517	$ 531	$ 1,073	$ 1,015
Diluted earnings per share	$ 2.85	$ 2.74	$ 5.88	$ 5.15
Contracts Accounted for under Percentage of Completion [Member]
Change in Accounting Estimate [Line Items]
Operating Income (Loss)	$ 137	$ 162	$ 266	$ 349
Net earnings	$ 89	$ 105	$ 173	$ 227
Diluted earnings per share	$ 0.49	$ 0.54	$ 0.95	$ 1.15