Note 13 - Goodwill and Intangible Assets - Summary of Changes in Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Goodwill, gross	$ 711	$ 710
Goodwill, Net additions	834	1
Goodwill	0	0
Accumulated goodwill impairment	(99)	(99)
Goodwill	$ 612	$ 611

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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Amount of divestiture 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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