CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 32,855	$ 16,264
Accounts receivable	66,082	42,929
Allowance for doubtful accounts	(377)	(378)
Accounts receivable, net	65,705	42,551
Inventories:
Finished goods	16,536	17,778
Raw materials	1,670	1,795
Total inventories	18,206	19,573
Supplies, prepaid items and other:
Prepaid insurance	1,879	12,315
Precious metals	10,670	6,787
Supplies	26,011	25,288
Other	7,629	6,802
Total supplies, prepaid items and other	46,189	51,192
Total current assets	162,955	129,580
Property, plant and equipment, net	869,497	891,198
Other assets:
Operating lease assets	28,308	26,403
Intangible and other assets, net	13,784	6,121
Total other assets	42,092	32,524
Total assets	1,074,544	1,053,302
Current liabilities:
Accounts payable	73,658	46,551
Short-term financing	1,083	13,576
Accrued and other liabilities	50,772	30,367
Current portion of long-term debt	9,249	16,801
Total current liabilities	134,762	107,295
Long-term debt, net	460,637	467,389
Noncurrent operating lease liabilities	20,704	19,845
Other noncurrent accrued and other liabilities	4,040	6,090
Deferred income taxes	31,333	30,939
Commitments and contingencies (Note 6)
Stockholders' equity:
Common stock, $.10 par value; 150 million shares authorized, 90 million shares issued (75 million shares authorized, 40 million shares issued at December 31, 2020)	8,983	3,991
Capital in excess of par value	489,107	197,352
Accumulated deficit	(71,461)	(41,487)
Stockholders equity including treasury stock	429,629	162,856
Less treasury stock, at cost:
Common stock, 1 million shares (2.1 million shares at December 31, 2020)	6,561	13,213
Total stockholders' equity	423,068	149,643
Total Liabilities and Stockholders' equity	1,074,544	1,053,302
Series E Preferred Stock [Member]
Redeemable preferred stocks:
Redeemable preferred stock, value		272,101
Series B Preferred Stock [Member]
Stockholders' equity:
Preferred stock, value	2,000	2,000
Series D Preferred Stock [Member]
Stockholders' equity:
Preferred stock, value	$ 1,000	$ 1,000