CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenues:
Royalties	$ 3,766	$ 8,133	$ 14,068	$ 24,811
Miscellaneous income	73	31	224	94
Total revenues	3,839	8,164	14,292	24,905
Operating expenses:
General and administrative	213	571	1,312	1,915
Lease termination costs	4,552	0	4,552	0
Total operating expenses	4,765	571	5,864	1,915
Operating income (loss)	(926)	7,593	8,428	22,990
Other income (expense):
Other, net	0	0	0	61
Total other income	0	0	0	61
Income (expense) before income tax expense	(926)	7,593	8,428	23,051
Income tax expense (benefit)	888	1	(712)	56
Net income (loss)	$ (1,814)	$ 7,592	$ 9,140	$ 22,995
Earnings (loss) per common share
Basic (in dollars per share)	$ (0.04)	$ 0.17	$ 0.21	$ 0.52
Diluted (in dollars per share)	$ (0.04)	$ 0.17	$ 0.21	$ 0.52
Weighted average number of shares
Weighted-average shares - basic (in shares)	44,182	44,131	44,182	44,109
Weighted-average shares - diluted (in shares)	44,182	44,239	44,214	44,254