Note 1 - Summary of Impact of Adoption on Consolidated Statement of Financial Position (Details) - USD ($) $ in Millions	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Basis Of Presentation And Recent Accounting Pronouncements [Line Items]
Operating lease right-of-use assets	$ 49
Operating lease liabilities	58
Deferred rent payable			$ 9
Deferred gain on previous sale leaseback transaction			6
Net fixed assets from previous sale leaseback transaction			1
Accumulated deficit	$ 213		$ 200
ASU 2016-02 [Member]
Basis Of Presentation And Recent Accounting Pronouncements [Line Items]
Operating lease right-of-use assets		$ 53
Operating lease liabilities		62
Accumulated deficit		195
ASU 2016-02 [Member] | Adjustments Due to ASU 2016-02 [Member]
Basis Of Presentation And Recent Accounting Pronouncements [Line Items]
Operating lease right-of-use assets		53
Operating lease liabilities		62
Deferred rent payable		(9)
Deferred gain on previous sale leaseback transaction		(6)
Net fixed assets from previous sale leaseback transaction		(1)
Accumulated deficit		$ (5)