Note 6 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

	For the Years Ended December 31,
	2021			2020			2019
Current:
U.S. Federal	$	13,769		$	(5,933	)	$	15,905
U.S. State		2,145			(2,294	)		4,717
Non-U.S.		143			514			1,336
		16,057			(7,713	)		21,958
Deferred:
U.S. Federal		(16,657	)		10,936			(9,386	)
U.S. State		1,897			749			(8,033	)
		(14,760	)		11,685			(17,419	)
Total Income Tax Expense	$	1,297		$	3,972		$	4,539

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	For the Years Ended December 31,
	2021						2020						2019
	Amount			Percent			Amount			Percent			Amount			Percent
Statutory U.S. federal income tax rate	$	7,436			21.0	%	$	(1,941	)		21.0	%	$	20,600			21.0	%
State income taxes, net of federal tax benefit		(642	)		(1.8	)		(1,109	)		12.0			3,125			3.2
Effect of foreign income taxes		125			0.4			406			(4.4	)		1,336			1.4
Excess tax depletion		(10,535	)		(29.8	)		—			—			(13,141	)		(13.4	)
Uncertain tax positions		1,473			4.2			—			—			—			—
Compensation		3,192			9.0			1,310			(14.2	)		1,799			1.8
Valuation allowance		(544	)		(1.5	)		1,479			(16.0	)		1,400			1.4
Tax credits		(210	)		(0.6	)		1,150			(12.4	)		(2,536	)		(2.6	)
Non-controlling interest		—			—			726			(7.9	)		(3,687	)		(3.8	)
State rate change and prior period adjustments		642			1.8			1,797			(19.4	)		(4,565	)		(4.6	)
Other		360			1.0			154			(1.6	)		208			0.2
Income Tax Expense / Effective Rate	$	1,297			3.7	%	$	3,972			(42.9	)%	$	4,539			4.6	%

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	December 31,
	2021			2020
Deferred Tax Asset:
Postretirement benefits other than pensions	$	84,130		$	101,673
Pneumoconiosis benefits		47,681			60,284
Asset retirement obligations		47,180			56,779
Workers' compensation		11,419			17,493
Compensation		5,203			5,158
State bonus, net of Federal		4,219			6,918
Long-term disability		1,931			2,757
Net operating loss		937			6,134
Operating lease liability		135			11,377
Mine subsidence		—			17,271
Salary retirement		—			9,446
Financing		—			2,077
Other		5,772			4,175
Total Deferred Tax Asset		208,607			301,542
Valuation Allowance		(937	)		(2,879	)
Net Deferred Tax Asset		207,670			298,663
Deferred Tax Liability:
Equity Partnerships		(99,811	)		(35,570	)
Property, plant and equipment		(40,064	)		(172,026	)
Advance mining royalties		(7,270	)		(10,908	)
Salary retirement		(2,739	)		—
Financing		(640	)		—
Right of use assets		(135	)		(11,338	)
Total Deferred Tax Liability		(150,659	)		(229,842	)
Net Deferred Tax Asset	$	57,011		$	68,821

Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]

	December 31,
	2021		2020
Balance at January 1	$	—	$	—
Additions based on tax positions related to the current year		774		—
Additions for tax positions of prior years		2,859		—
Reductions for tax positions of prior years		—		—
Reductions due to the statute of limitations		—		—
Settlements		—		—
Balance at December 31	$	3,633	$	—