Pensions and Other Employee Benefits, Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Net loss (gain)	$ 60
Prior service cost (credit)	0
Total amount expected to be amortized	60
Pension Plans [Member]
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Net loss (gain)	179	$ (132)	$ 560
Prior service cost (credit)	15	0	1
Amortization of net (loss) gain	(52)	(68)	(17)
Amortization of prior service (cost) credit	0	(1)	(2)
Total recognized in other comprehensive income	142	(201)	542
Total recognized in net periodic benefit cost and other comprehensive income	239	(62)	622
Net loss (gain)	62
Prior service cost (credit)	1
Total amount expected to be amortized	63
Postretirement Benefit Plans [Member]
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Net loss (gain)	(4)	(7)	5
Prior service cost (credit)	(2)	0	(1)
Amortization of net (loss) gain	2	0	2
Amortization of prior service (cost) credit	2	2	2
Total recognized in other comprehensive income	(2)	(5)	8
Total recognized in net periodic benefit cost and other comprehensive income	(2)	$ (2)	$ 10
Net loss (gain)	(2)
Prior service cost (credit)	(1)
Total amount expected to be amortized	$ (3)