Shareholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Preferred Shares [Abstract]
Preferred shares, shares authorized (in shares)	2,000,000		2,000,000
Series A Convertible Preferred shares outstanding (in shares)	70,000		70,000
Common Shares [Abstract]
Common shares, authorized (in shares)	125,000,000		125,000,000
Common shares, par value (in dollars per share)	$ 0		$ 0
Common shares, shares issued (in shares)	83,281,000		83,122,000
Common shares, shares outstanding (in shares)	78,387,000		78,228,000
Treasury stock (in shares)	4,894,000		4,894,000
Stock options granted (in shares)	550,000	1,205,000
Options exercised (in shares)	155,532
Warrants exercised (in shares)	3,897
Proceeds from exercises of stock options	$ 621	$ 220
Proceeds from exercise of warrants	$ 19	$ 0
Series A Preferred Stock [Member]
Preferred Shares [Abstract]
Series A Convertible Preferred shares outstanding (in shares)	70,000
Preferred stock dividend rate (in hundredths)	3.00%
Preferred share dividend (in dollars per shares)	$ 1.50
Share conversion price (in dollars per share)	$ 4.00
Common stock conversion ratio	12.5