Inventories (Schedule Of Inventories) (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Inventories [Abstract]
Finished products	$ 65,687,000	$ 71,743,000
Work in process	17,000,000	16,494,000
Raw materials and supplies	58,788,000	62,344,000
Total inventories	141,475,000	150,581,000
Excess of FIFO costs over LIFO costs	47,368,000	45,820,000
Total FIFO inventories	188,843,000	196,401,000
Percentage of LIFO inventories on total inventories	18.00%	22.00%
Effect of LIFO liquidations, reduced cost of sales	500,000
Effect of LIFO liquidations, increased net income	$ 300,000