Retirement Plans (Schedule Of Net Periodic Benefit Cost And Other Comprehensive Loss (Earnings) For Pension And Other Postretirement Benefit Plans) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Pension Benefits [Member]
Net periodic benefit cost:
Service cost		$ 15	$ 33	$ 30
Interest cost		42	52	55
Expected return on plan assets		(55)	(58)	(54)
Curtailment and settlement expense				1
Recognition of net actuarial loss (gain)	[1]	25	20	18
Recognition of prior service cost	[1]	3	4	4
Total net periodic benefit cost	[2]	30	51	54
Other comprehensive loss (earnings):
Actuarial loss (gain) arising in current year		26	5	57
Prior service cost (credit) arising in current year		2
Recognition of net actuarial loss, including settlement expense, in net periodic benefit cost	[3]	(43)	(20)	(19)
Recognition of prior service cost, including curtailment, in net periodic benefit cost	[3]	(9)	(4)	(4)
Total other comprehensive loss (earnings)		(24)	(19)	34
Total recognized		6	32	88
Postretirement Benefits [Member]
Net periodic benefit cost:
Service cost			1	1
Interest cost		1	1	1
Recognition of net actuarial loss (gain)	[1]	(1)	(1)	(1)
Recognition of prior service cost	[1]	(1)	(2)	(2)
Total net periodic benefit cost	[2]	(1)	(1)	(1)
Other comprehensive loss (earnings):
Actuarial loss (gain) arising in current year			(1)
Prior service cost (credit) arising in current year			1
Recognition of net actuarial loss, including settlement expense, in net periodic benefit cost	[3]	1	1	1
Recognition of prior service cost, including curtailment, in net periodic benefit cost	[3]	1	1	2
Total other comprehensive loss (earnings)		2	2	3
Total recognized		$ 1	$ 1	$ 2

[1] These net periodic benefit costs were reclassified out of other comprehensive earnings in the current period.

[2] Net periodic benefit cost is a component of G&A on the accompanying consolidated comprehensive statements of earnings.

[3] These amounts include restructuring costs that were reclassified out of other comprehensive earnings in the current period. See Note 6 for further discussion.