CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
General and administrative expense	$ 4,687	$ 3,962	$ 14,764	$ 13,596
Operating loss	(4,687)	(3,962)	(14,764)	(13,596)
Other income (loss), net	(2,405)	704	(1,746)	301
Interest income	513	398	1,460	1,487
Interest expense	(1,161)	(1,133)	(3,465)	(3,383)
Equity income (loss)	(16,345)	(7,635)	17,954	(30,062)
Net loss before income taxes	(24,085)	(11,628)	(561)	(45,253)
Income tax benefit (expense)	0	0	0	0
Net loss	$ (24,085)	$ (11,628)	$ (561)	$ (45,253)
Net loss per share:
Basic (in dollars per share)	$ (1.18)	$ (0.56)	$ (0.03)	$ (2.17)
Diluted (in dollars per share)	$ (1.18)	$ (0.56)	$ (0.03)	$ (2.17)
Weighted average shares used in computing loss per share:
Basic (in shares)	20,387	20,919	20,390	20,892
Diluted (in shares)	20,387	20,919	20,390	20,892