Inventories (Details) (USD $)	Sep. 30, 2011	Dec. 31, 2010
Gross inventories @ FIFO:
Finished goods	$ 8,958,000	$ 7,757,000
Work in progress	35,266,000	26,680,000
Raw materials & component parts	127,491,000	99,440,000
Maintenance, tooling & supplies	16,057,000	14,156,000
Total gross inventories @ FIFO	187,772,000	148,033,000
Less reserves:
LIFO	33,864,000	28,776,000
Valuation	2,565,000	2,383,000
Total inventories as reported	151,343,000	116,874,000
Gross inventories on FIFO basis accounted for on a LIFO basis	$ 107,600,000	$ 80,900,000