v3.22.0.1

Income Taxes - Expiration Periods of Deferred Tax Asset​s (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred Tax Asset Expiration [Line Items]
Tax loss carryforwards	$ 206	$ 167
Employee benefits	331	503
Other	175
Valuation allowance	(90)	(91)	$ (113)	$ (107)
Deferred tax assets, net	622	$ 694
Expires within 10 years
Deferred Tax Asset Expiration [Line Items]
Tax loss carryforwards	34
Employee benefits	0
Other	0
Valuation allowance	(32)
Deferred tax assets, net	2
Expires within 11-20 years
Deferred Tax Asset Expiration [Line Items]
Tax loss carryforwards	30
Employee benefits	0
Other	2
Valuation allowance	(6)
Deferred tax assets, net	26
No Expiration
Deferred Tax Asset Expiration [Line Items]
Tax loss carryforwards	142
Employee benefits	0
Other	44
Valuation allowance	(5)
Deferred tax assets, net	181
Other
Deferred Tax Asset Expiration [Line Items]
Tax loss carryforwards	0
Employee benefits	331
Other	129
Valuation allowance	(47)
Deferred tax assets, net	$ 413

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- Definition

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+ References

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- Definition

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+ References

No definition available.

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- Definition

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

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- Definition

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32632-109319

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32621-109319

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- Definition

Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences from employee benefits, classified as other.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 6
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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

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