CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Statement [Abstract]
General and administrative expense	$ 3,758	$ 4,687	$ 13,191	$ 14,764
Operating loss	(3,758)	(4,687)	(13,191)	(14,764)
Other loss	(379)	(2,405)	(219)	(1,746)
Interest income	1,004	513	2,892	1,460
Interest expense	(2,643)	(1,161)	(5,953)	(3,465)
Equity income (loss)	(12,874)	(16,345)	(53,373)	17,954
Net loss before income taxes	(18,650)	(24,085)	(69,844)	(561)
Income tax benefit (expense)	0	0	0	0
Net loss	$ (18,650)	$ (24,085)	$ (69,844)	$ (561)
Net loss per share:
Basic (in dollars per share)	$ (0.91)	$ (1.18)	$ (3.42)	$ (0.03)
Diluted (in dollars per share)	$ (0.91)	$ (1.18)	$ (3.42)	$ (0.03)
Weighted average shares used in computing loss per share:
Basic (in shares)	20,455	20,387	20,416	20,390
Diluted (in shares)	20,455	20,387	20,416	20,390