Income Taxes - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Statutory tax rate	25.00%	19.00%	19.00%
Increase in valuation allowance	$ 5
Unremitted earnings	37	$ 28
Benefit realized from tax holiday granted	$ 97	$ 90	$ 77
Earnings per share impact of tax holiday (in dollars per share)	$ 0.42	$ 0.37	$ 0.31
Unrecognized tax benefits that would impact effective tax rate	$ 270	$ 248	$ 228
Accrued potential interest and penalties	21	24	22
Liability recorded for interest and penalties	$ 120	$ 99	$ 77

Represents the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions.

No definition available.

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- Definition

Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiary and other recognized entity not within country of domicile. Includes, but is not limited to, other basis differences.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.Fact.4)
-URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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- References

No definition available.

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- Definition

Per share amount effect of the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330215-122817

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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- Definition

Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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