Condensed Consolidated Balance Sheets (Parenthetical) (Unaudited) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Statement of Financial Position [Abstract]
Common shares, par value (dollars per share)	$ 0	$ 0	$ 0
Common shares, shares authorized (shares)	42,000,000	42,000,000	42,000,000
Common shares, shares issued (shares)	19,198,000	19,198,000	19,198,000
Preferred shares, par value (dollars per share)	$ 0	$ 0	$ 0
Preferred shares, shares authorized (shares)	1,000,000	1,000,000	1,000,000
Preferred shares, shares issued (shares)	0	0	0
Treasury shares, at cost (shares)	456,000	554,000	557,000