Share-Based Compensation Plans Textuals (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense from share-based compensation awards	$ 3.6
Weighted-average period of recognition of unrecognized compensation expense (in years)	2 years 3 months 10 days
Restricted shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense from share-based compensation awards	$ 2.2
Weighted-average period of recognition of unrecognized compensation expense (in years)	1 year 11 months 20 days