Note 1 - Organization and Summary of Significant Accounting Policies - Effect of Error Correction on Financial Statements (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Net income (loss)	$ (173)	$ 38	$ (66)	$ (135)	$ 35
Less: Noncontrolling interests net income		2	2	2	6
Less: Redeemable noncontrolling interests net income (loss)	1	(22)		(21)	(1)
Net income attributable to the parent company	$ (174)	$ 58	$ (68)	$ (116)	$ 30
Basic (in dollars per share)	$ (1.20)	$ 0.40	$ (0.47)	$ (0.80)	$ 0.21
Diluted (in dollars per share)	$ (1.20)	$ 0.40	$ (0.47)	$ (0.80)	$ 0.21
Total comprehensive loss	$ (152)	$ (84)	$ 294	$ (236)	$ 432
Less: Comprehensive (income) loss attributable to noncontrolling interests	(9)	17	(3)	8	(5)
Less: Comprehensive (income) loss attributable to redeemable noncontrolling interests	3	14	1	17	(3)
Comprehensive income (loss) attributable to the parent company	(158)	(53)	$ 292	(211)	$ 424
Redeemable noncontrolling interests	159	155		159		$ 167
Retained earnings	$ 490	664		$ 490		$ 622
Previously Reported [Member]
Net income (loss)		38
Less: Noncontrolling interests net income		2
Less: Redeemable noncontrolling interests net income (loss)		(2)
Net income attributable to the parent company		$ 38
Basic (in dollars per share)		$ 0.26
Diluted (in dollars per share)		$ 0.26
Total comprehensive loss		$ (84)
Less: Comprehensive (income) loss attributable to noncontrolling interests		17
Less: Comprehensive (income) loss attributable to redeemable noncontrolling interests		(6)
Comprehensive income (loss) attributable to the parent company		(73)
Redeemable noncontrolling interests		175
Retained earnings		644
Revision of Prior Period, Adjustment [Member]
Net income (loss)		0
Less: Noncontrolling interests net income
Less: Redeemable noncontrolling interests net income (loss)		(20)
Net income attributable to the parent company		$ 20
Basic (in dollars per share)		$ 0.14
Diluted (in dollars per share)		$ 0.14
Total comprehensive loss		$ 0
Less: Comprehensive (income) loss attributable to noncontrolling interests
Less: Comprehensive (income) loss attributable to redeemable noncontrolling interests		20
Comprehensive income (loss) attributable to the parent company		20
Redeemable noncontrolling interests		(20)
Retained earnings		$ 20