Share-Based Compensation Employee Share-Based Compensation Plans (Details)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award
Options granted (in shares)	590,000
2008 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Options granted (in shares)	590,000	162,600
Remaining shares available for grant under the plan (in shares)	2,991,200
2011 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Options granted (in shares)	0	300,000
Amended and Restated 2011 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Remaining shares available for grant under the plan (in shares)	1,225,250