Note 11 - Goodwill and Intangible Assets - Summary of Changes in Goodwill (Details) $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($)
Goodwill, gross	$ 1,545
Goodwill, Net additions	2
Goodwill	0
Goodwill, gross	1,547
Accumulated goodwill impairmant	(99)
Accumulated goodwill impairmant	(99)
Goodwill	1,446
Goodwill	$ 1,448

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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Amount before 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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