UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenues:
Marketing	$ 438,791	$ 301,176	$ 812,429	$ 589,791
Transportation	13,626	13,616	27,244	27,071
Oil and natural gas	0	410	0	1,427
Total revenues	452,417	315,202	839,673	618,289
Costs and expenses:
Marketing	431,683	297,508	800,866	582,661
Transportation	11,890	11,851	24,191	24,013
Oil and natural gas	0	201	0	951
General and administrative	2,284	1,460	4,567	4,097
Depreciation, depletion and amortization	2,262	3,563	4,674	7,532
Total costs and expenses	448,119	314,583	834,298	619,254
Operating earnings (losses)	4,298	619	5,375	(965)
Other income (expense):
Loss on deconsolidation of subsidiary	0	(1,635)	0	(1,635)
Interest income	498	260	885	419
Interest expense	(15)	(1)	(34)	(2)
Total other income (expense), net	483	(1,376)	851	(1,218)
(Losses) earnings before income taxes	4,781	(757)	6,226	(2,183)
Income tax benefit (provision)	(1,161)	475	(1,468)	1,041
Net (losses) earnings	$ 3,620	$ (282)	$ 4,758	$ (1,142)
Earnings (losses) per share:
Basic net (losses) earnings per common share (in dollars per share)	$ 0.86	$ (0.07)	$ 1.13	$ (0.27)
Diluted net (losses) earnings per common share (in dollars per share)	0.86	(0.07)	1.13	(0.27)
Dividends per common share (in dollars per share)	$ 0.22	$ 0.22	$ 0.44	$ 0.44