Equity Accumulated Other Comprehensive Loss (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jan. 01, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Retained Earnings (Accumulated Deficit)	$ (1,525,000,000)		$ (2,209,000,000)	$ (2,276,000,000)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	49,000,000
Other Comprehensive Income (Loss), Net of Tax	78,000,000	$ 92,000,000
Unfunded pension obligation, Net of Tax	(55,000,000)			(57,000,000)
Foreign currency translation adjustment, Net of Tax	(1,483,000,000)			(1,486,000,000)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(1,808,000,000)		(1,857,000,000)	(1,876,000,000)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	56,000,000
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax	(270,000,000)			$ (333,000,000)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(7,000,000)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	9,000,000	71,000,000
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	57,000,000	(5,000,000)
Total pension adjustments, net of income tax	2,000,000	$ 6,000,000
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	3,000,000
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	37,000,000
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	7,000,000
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	44,000,000
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	2,000,000
Total pension adjustments, net of income tax	2,000,000
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	19,000,000
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(16,000,000)
Alto Maipo [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(33,000,000)
ASC 606 Impact [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Retained Earnings (Accumulated Deficit)	76,000,000		67,000,000
Accumulated Other Comprehensive Income (Loss), Net of Tax	19,000,000		$ 19,000,000
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	19,000,000
ASC 606 Impact [Member] | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	19,000,000
ASC 606 Impact [Member] | Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	$ 0