Note 8 - Revenues (Tables)

6 Months Ended

Jun. 30, 2020

Revenue from Contract with Customer [Abstract]

Schedule of disaggregation of revenue

	Three months ended June 30,				Six months ended June 30,
(In thousands)	2020		2019		2020		2019
Coal Sales
Domestic revenues	$	20,686	$	39,544	$	51,218	$	76,116
Export revenues		15,688		26,217		27,092		47,105
Total revenues	$	36,374	$	65,761	$	78,310	$	123,221