Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2016
Income Tax Disclosures [Line Items]
Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Percent		0.06
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	15.00%	12.00%	9.00%
Effective tax rate	44.00%	35.00%	35.00%
Increase (decrease) in valuation allowance	$ (190,000,000)	$ (44,000,000)
Valuation allowance	(634,000,000)	(824,000,000)
Income tax expense	$ (216,000,000)	$ (352,000,000)	$ (708,000,000)
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	21.00%
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	$ 0.04
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued:
Interest on income taxes accrued	$ 1,000,000	$ 2,000,000
Unrecognized Tax Benefits, Income Tax Penalties Accrued	0	0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense:
Unrecognized Tax Benefits, Income Tax Penalties Expense	0	0	$ 0
Uncertain Tax Positions Additional Disclosures:
Unrecognized tax benefits	458,000,000	465,000,000	463,000,000	$ 348,000,000
Unrecognized tax benefits that would impact effective tax rate	439,000,000	448,000,000	446,000,000
Unrecognized tax benefits that would impact effective tax rate portion with attributes warranting full valuation allowance	33,000,000
Unrecognized Tax benefits Anticipated To Result In Ne Decrease of Unrecognized Tax Benefits WIthin 12 Months of Balance Sheet Date Minimum	0
Unrecognized tax benefits anticipated to result in net decrease of unrecognized tax benefits within 12 months, maximum	10,000,000
Federal
Income Tax Disclosures [Line Items]
Operating loss carryforward	2,100,000,000
Foreign Tax Authority
Income Tax Disclosures [Line Items]
Operating loss carryforward	2,000,000,000.0
State and Local Jurisdiction
Income Tax Disclosures [Line Items]
Operating loss carryforward	7,300,000,000
General Business Tax Credit Carryforward
Income Tax Disclosures [Line Items]
Tax credit carryforward	66,000,000
Foreign Jurisdictions
Income Tax Disclosures [Line Items]
Tax credit carryforward	14,000,000
2021 Expiration | Foreign Jurisdictions
Income Tax Disclosures [Line Items]
Tax credit carryforward	13,000,000
Non-US [Member]
Income Tax Disclosures [Line Items]
Income tax expense	(33,000,000)	(26,000,000)	(35,000,000)
VIET NAM
Income Tax Disclosures [Line Items]
Income tax expense	$ (16,000,000)	$ (13,000,000)	$ (19,000,000)
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	$ 0.01
Earliest Tax Year | Federal
Uncertain Tax Positions Additional Disclosures:
Operating Loss Carryforwards, Limitations on Use	950 million
Earliest Tax Year | General Business Tax Credit Carryforward
Income Tax Disclosures [Line Items]
Tax credit carryforward	$ 16,000,000
Latest Tax Year | Federal
Uncertain Tax Positions Additional Disclosures:
Operating Loss Carryforwards, Limitations on Use	1.2 billion
Latest Tax Year | General Business Tax Credit Carryforward
Income Tax Disclosures [Line Items]
Tax credit carryforward	$ 50,000,000
Guacolda Affiliate [Member]
Income Tax Disclosures [Line Items]
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent	(1.00%)
UNITED STATES
Income Tax Disclosures [Line Items]
Tax Cuts and Jobs Act, Transition Tax for Accumulated Foreign Earnings, Income Tax Expense	$ 124,000,000
Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Percent		0.09
Tax Cuts and Jobs Act, Income Tax Expense (Benefit)		$ 194,000,000
Effective tax rate	35.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%
Tax Cuts and Jobs Act, Measurement Period Adjustment, Income Tax Expense (Benefit)		$ 77,000,000
Uncertain Tax Positions Additional Disclosures:
Unrecognized tax benefits that would impact effective tax rate	$ 161,000,000