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Income Taxes NOL and Tax Credit Carryforwards (Details) $ in Millions	Dec. 31, 2020 USD ($)
United States
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	$ 800
State [Member]
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	146
Tax credit carryforwards	11
UNITED KINGDOM
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	39
Within 5 years [Member] | United States
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	0
Within 5 years [Member] | State [Member]
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	31
Tax credit carryforwards	3
Within 5 years [Member] | UNITED KINGDOM
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	0
Indefinite Expiration Period, Within 5 Years | United States
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	0
Indefinite Expiration Period, Within 5 Years | State [Member]
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	0
Within 5-20 years [Member] | United States
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	800
Within 5-20 years [Member] | State [Member]
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	115
Tax credit carryforwards	8
Within 5-20 years [Member] | UNITED KINGDOM
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	0
Indefinite Expiration Period | United States
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	126
Indefinite Expiration Period | State [Member]
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	1
Indefinite Expiration Period, 5-20 Years | United States
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	0
Indefinite Expiration Period, 5-20 Years | State [Member]
NOL and Tax Credit Carryforwards [Line Items]
Operating loss carryforwards	0
Foreign Tax Credits [Member] | United States
NOL and Tax Credit Carryforwards [Line Items]
Tax credit carryforwards	22
Foreign Tax Credits [Member] | Within 5 years [Member] | United States
NOL and Tax Credit Carryforwards [Line Items]
Tax credit carryforwards	5
Foreign Tax Credits [Member] | Within 5-20 years [Member] | United States
NOL and Tax Credit Carryforwards [Line Items]
Tax credit carryforwards	17
Research Tax Credit Carryforward [Member] | United States
NOL and Tax Credit Carryforwards [Line Items]
Tax credit carryforwards	4
Research Tax Credit Carryforward [Member] | Within 5 years [Member] | United States
NOL and Tax Credit Carryforwards [Line Items]
Tax credit carryforwards	0
Research Tax Credit Carryforward [Member] | Within 5-20 years [Member] | United States
NOL and Tax Credit Carryforwards [Line Items]
Tax credit carryforwards	4
Economic Zone Credit [Member] | Poland [Member]
NOL and Tax Credit Carryforwards [Line Items]
Tax credit carryforwards	3
Economic Zone Credit [Member] | Within 5 years [Member] | Poland [Member]
NOL and Tax Credit Carryforwards [Line Items]
Tax credit carryforwards	0
Economic Zone Credit [Member] | Within 5-20 years [Member] | Poland [Member]
NOL and Tax Credit Carryforwards [Line Items]
Tax credit carryforwards	$ 3

X

- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
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