Note 9 - Schedule of Information Related to Lease Costs for Finance and Operating Leases (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2019
Finance lease cost
Amortization of leased assets	$ 1	$ 3
Operating lease cost	6	19
Variable lease cost	2	5
Total lease cost	$ 9	$ 27

Amount of amortization expense attributable to right-of-use asset from finance lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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- References

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Section 50
-Paragraph 4
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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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