Inventory Cost, LIFO Versus FIFO (Details) (USD $)	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
LIFO Method Related Items [Abstract]
Percentage of LIFO inventory	96.00%	96.00%
Inventory, LIFO reserve	$ 14,693,000	$ 14,541,000
Effect of LIFO inventory liquidation on income	$ 100,000