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Note 7 - Income Taxes - Schedule of Unrecognized Tax Benefits Assets (Liabilities) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Balance, Unrecognized tax benefits	$ 74	$ 64	$ 174
Decreases for positions taken in prior years	(24)	(19)	(96)
Refunds from/(payments to) and settlements with taxing authorities	(12)	0	(11)
Increases for positions taken in current year	3	18	20
Increases/(decreases) for interest and penalties	(3)	5	(5)
Increases for positions taken in prior years	1	7	44
Lapse of statutes of limitations	(1)	(1)	(62)
Balance, Unrecognized tax benefits	$ 38	$ 74	$ 64

X

- Definition

Amount of increase (decrease) in unrecognized tax benefits resulting from the increase (decrease) in interest and penalties.

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Amount of increase(decrease)in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 10B
-URI http://asc.fasb.org/extlink&oid=123427490&loc=SL37586934-109318

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319

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+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319

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+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 15A
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+ References

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-Section 50
-Paragraph 15A
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-URI http://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319

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+ 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 (a)(4)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319

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