Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
General and administrative expense	$ 1,991	$ 2,028	$ 4,454	$ 5,560
Operating loss	(1,991)	(2,028)	(4,454)	(5,560)
Other income (loss), net	6,733	(2,658)	7,439	(6,225)
Interest income	74	52	127	157
Equity income (loss), net	(5,136)	(5,277)	14,193	(14,291)
Net income (loss) before income taxes	(320)	(9,911)	17,305	(25,919)
Income tax benefit (expense)	0	0	0	0
Net income (loss)	$ (320)	$ (9,911)	$ 17,305	$ (25,919)
Net income (loss) per share:
Basic (in dollars per share)	$ (0.02)	$ (0.48)	$ 0.83	$ (1.25)
Diluted (in dollars per share)	$ (0.02)	$ (0.48)	$ 0.83	$ (1.25)
Weighted average shares used in computing income (loss) per share:
Basic (in shares)	20,856	20,720	20,879	20,703
Diluted (in shares)	20,856	20,720	20,879	20,703