Shareholders' Equity, Stock Plans and Preferred Stock (Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding and Exercisable) (Details) - Stock Options and Stock Appreciation Rights (SARs) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at beginning of period (in shares)	211	211	231
Granted (in shares)	0
Exercised (in shares)	(1)
Expired or cancelled (in shares)	(19)
Outstanding at end of period (in shares)	211
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted-Average Exercise Price, Outstanding at beginning of period (in dollars per share)	$ 6.97
Weighted-Average Exercise Price, Granted (in dollars per share)	0.00
Weighted-Average Exercise Price, Exercised (in dollars per share)	3.91
Weighted-Average Exercise Price, Expired or cancelled (in dollars per share)	10.73
Weighted-Average Exercise Price, Outstanding at end of period (in dollars per share)	$ 6.64
Number of Shares, Exercisable (in shares)		211
Weighted-Average Exercise Price, Exercisable (in dollars per share)		$ 6.64