Condensed Consolidated Statements of Financial Position (Parenthetical) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010
Current Assets
Allowances for accounts receivable	$ 4,126	$ 2,950
Shareholders' Equity
Preferred Shares, shares authorized	1,000,000	1,000,000
Preferred Shares, shares issued
Preferred Shares, shares outstanding
Common Shares, par value
Common Shares, shares authorized	60,000,000	60,000,000
Common Shares, shares outstanding	33,572,151	35,315,732
Treasury Shares, shares	4,340,506	2,592,175