Income Taxes (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosures [Line Items]
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Percent			90.00%	12.00%	0.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			10.00%	10.00%	(5.00%)
Effective Income Tax Rate Reconciliation Withholding Tax Reversals			0.00%	31.00%	3.00%
Deferred Tax Liabilities, Undistributed Foreign Earnings			$ 0
Undistributed Earnings of Foreign Subsidiaries			$ 4,000,000,000
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent			0.00%	(46.00%)	5.00%
Effective tax rate			128.00%	17.00%	42.00%
Increase (decrease) in valuation allowance			$ (112,000,000)	$ (18,000,000)
Valuation allowance			988,000,000	876,000,000
Tax benefits related to tax status of operations in countries subject to reduced tax rates			26,000,000	20,000,000	$ 21,000,000
Income tax expense			$ (990,000,000)	$ (32,000,000)	$ (412,000,000)
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			35.00%	35.00%	35.00%
Tax benefits related to tax status of operations in countries subject to reduced tax rates per share (in dollars per share)			$ 0.03	$ 0.02	$ 0.02
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued:
Interest on income taxes accrued			$ 7,000,000	$ 6,000,000
Unrecognized Tax Benefits, Income Tax Penalties Accrued			0	0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense:
Unrecognized Tax Benefits, Interest on Income Taxes Expense			1,000,000	2,000,000	$ 2,000,000
Unrecognized Tax Benefits, Income Tax Penalties Expense			0	0	0
Uncertain Tax Positions Additional Disclosures:
Unrecognized tax benefits			348,000,000	352,000,000	364,000,000	$ 384,000,000
Unrecognized tax benefits that would impact effective tax rate			332,000,000	332,000,000	343,000,000
Unrecognized tax benefits that would impact effective tax rate portion with attributes warranting full valuation allowance			29,000,000	24,000,000	24,000,000
Unrecognized Tax benefits Anticipated To Result In Ne Decrease of Unrecognized Tax Benefits WIthin 12 Months of Balance Sheet Date Minimum			5,000,000
Unrecognized tax benefits anticipated to result in net decrease of unrecognized tax benefits within 12 months, maximum			15,000,000
Federal
Income Tax Disclosures [Line Items]
Operating loss carryforwards			1,900,000,000
State and Local Jurisdiction
Income Tax Disclosures [Line Items]
Operating loss carryforwards			9,300,000,000
Foreign Tax Authority
Income Tax Disclosures [Line Items]
Operating loss carryforwards			2,800,000,000
General Business Tax Credit Carryforward
Income Tax Disclosures [Line Items]
Tax credit carryforward			21,000,000
Federal Alternative Minimum Tax
Income Tax Disclosures [Line Items]
Tax credit carryforward			5,000,000
Foreign Jurisdictions
Income Tax Disclosures [Line Items]
Tax credit carryforward			28,000,000
2021 Expiration | Foreign Jurisdictions
Income Tax Disclosures [Line Items]
Tax credit carryforward			18,000,000
Year 2023 to 2028 [Member] | Foreign Jurisdictions
Income Tax Disclosures [Line Items]
Tax credit carryforward			1,000,000
No Expiration
Income Tax Disclosures [Line Items]
Tax credit carryforward			9,000,000
VIET NAM
Income Tax Disclosures [Line Items]
Income tax expense			$ (13,000,000)	$ (15,000,000)	$ (8,000,000)
Tax benefits related to tax status of operations in countries subject to reduced tax rates per share (in dollars per share)				$ 0.01	$ 0.01
Chilean tax reform Member [Member]
Income Tax Disclosures [Line Items]
Effective tax rate	25.00%		25.50%
Other Tax Expense (Benefit)	$ 26,000,000
Subsequent Event [Member] | Chilean tax reform Member [Member]
Income Tax Disclosures [Line Items]
Effective tax rate		27.00%
UNITED STATES
Income Tax Disclosures [Line Items]
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Percent			88.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			5.00%
Income tax expense			$ (714,000,000)
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount			$ 39,000,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount			$ 675,000,000
ARGENTINA
Income Tax Disclosures [Line Items]
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Percent			3.00%
Effective tax rate			35.00%
Income tax expense			$ 0
ARGENTINA | FY 2018 - 2019 [Member]
Income Tax Disclosures [Line Items]
Effective tax rate			30.00%
ARGENTINA | FY 2020 and beyond [Member]
Income Tax Disclosures [Line Items]
Effective tax rate			25.00%
Cash, Restricted Cash, Unbilled Receivables, and Other Liquid Assets [Member] | UNITED STATES
Income Tax Disclosures [Line Items]
Effective tax rate			15.50%
Non-cash [Member] | UNITED STATES
Income Tax Disclosures [Line Items]
Effective tax rate			8.00%