Condensed Consolidated Balance Sheets (Parenthetical) (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011
Statement of Financial Position [Abstract]
Common shares, par value (dollars per share)	$ 0	$ 0	$ 0
Common shares, shares authorized (shares)	42,000	42,000	42,000
Common shares, shares issued (shares)	19,198	19,198	19,198
Preferred shares, par value (dollars per share)	$ 0	$ 0	$ 0
Preferred shares, shares authorized (shares)	1,000	1,000	1,000
Preferred shares, shares issued (shares)	0	0	0
Treasury shares, at cost (shares)	557	697	701