Note 13 - Goodwill and Intangible Assets - Summary of Changes in Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Goodwill, gross	$ 1,545	$ 711
Goodwill, Net additions	14	834
Goodwill	0	0
Goodwill, gross	1,559	1,545
Accumulated goodwill impairment	(99)	(99)
Accumulated goodwill impairment	(99)	(99)
Goodwill	1,446	612
Goodwill	$ 1,460	$ 1,446

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Publisher FASB
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-Subparagraph (SX 210.9-03(10)(1))
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