Note 12 - Goodwill and Intangible Assets - Summary of Changes in Goodwill (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Goodwill, gross	$ 711
Goodwill, Net additions	822
Goodwill, gross	1,533
Accumulated goodwill impairmant	(99)
Accumulated goodwill impairmant	(99)
Goodwill	612
Goodwill	$ 1,434

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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