Share Based Compensation Plans (Options Outstanding, Range of Exercise Price) (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) $ / shares shares
Options Outstanding
Number of options outstanding (in shares) | shares	507,492
Weighted-average remaining contractual life (in years)	2 years 9 months 29 days
Weighted average exercise price (in usd per share)	$ 21.26
Intrinsic value | $	$ 3
Options Exercisable
Number of options exercisable (in shares) | shares	142,859
Weighted-average remaining contractual life (in years)	2 years 10 months 28 days
Weighted average exercise price (in usd per share)	$ 16.65
Intrinsic value | $	$ 2
Exercise Price Range ($12.79-$19.85) [Member]
Options Outstanding
Number of options outstanding (in shares) | shares	311,142
Weighted-average remaining contractual life (in years)	1 year 10 months 21 days
Weighted average exercise price (in usd per share)	$ 17.24
Intrinsic value | $	$ 3
Options Exercisable
Number of options exercisable (in shares) | shares	139,484
Weighted-average remaining contractual life (in years)	1 year 3 months 4 days
Weighted average exercise price (in usd per share)	$ 16.50
Intrinsic value | $	$ 2
Range of exercise price, minimum	$ 12.79
Range of exercise price, maximum	$ 19.85
Exercise Price Range ($20.34-$28.17) [Member]
Options Outstanding
Number of options outstanding (in shares) | shares	196,350
Weighted-average remaining contractual life (in years)	4 years 3 months 26 days
Weighted average exercise price (in usd per share)	$ 27.62
Intrinsic value | $	$ 0
Options Exercisable
Number of options exercisable (in shares) | shares	3,375
Weighted-average remaining contractual life (in years)	3 years 5 months 12 days
Weighted average exercise price (in usd per share)	$ 22.99
Intrinsic value | $	$ 0
Range of exercise price, minimum	$ 20.34
Range of exercise price, maximum	$ 28.17