Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Feb. 28, 2015	May 31, 2014
Accounts receivable, allowance	$ 477	$ 581
Preferred stock, par value	$ 1.00	$ 1.00
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Common stock in treasury	0us-gaap_TreasuryStockShares	1us-gaap_TreasuryStockShares
Common Stock
Common stock, par value	$ 0.05	$ 0.05
Common stock, shares issued	11,529	11,835
Class B Common Stock
Common stock, par value	$ 0.05	$ 0.05
Common stock, shares issued	2,141	2,191

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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