CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Accounts receivable, reserves	$ 1,671	$ 1,485
Preferred Shares, without par value
Preferred Shares, authorized	5,000	5,000
Preferred Shares, issued
Common Shares, without par value
Common Shares, authorized	60,000	60,000
Common Shares, issued	28,387	27,097
Common Shares, outstanding	28,014	26,222
Common shares held in treasury, shares	373	875

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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