Inventories (Tables)

12 Months Ended

Dec. 31, 2023

Inventory Disclosure [Abstract]

Schedule of inventories

Inventories consist of the following:

(In thousands)	December 31 2023		December 31 2022
Finished goods	$	15,565	$	11,809
Work-in-process	1,114		2,030
Raw materials and purchased parts	23,542		27,946
Stores and supplies	46,071		39,590
Total inventories	$	86,292	$	81,375
Valued at lower of cost or market:
LIFO basis	$	10,532	$	15,473
FIFO basis	9,265		8,826
Average cost basis	66,495		57,076
Total inventories	$	86,292	$	81,375