Supplemental Financial Information (Other Operating (Income) Expense, Net) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
UTIS fire
Fixed assets write-offs	$ 0	$ 0	$ 891	$ 0
Inventory charges	43	0	363	0
Professional services	577	0	2,171	0
Lease obligations	60	0	600	0
Lease impairments	495	0	495	0
Compensation & benefits	614	0	1,458	0
Third-party property claims	4,650	0	4,650	0
Other	0	0	76	0
Insurance recoveries	(5,017)	0	(6,495)	0
Total UTIS fire	1,422	0	4,209	0
(Gain) loss on sale or disposal of property, plant and equipment	9	(4)	(673)	49
Economic incentive grants	0	0	0	(145)
Total other operating (income) expense, net	$ 1,431	$ (4)	$ 3,536	$ (96)