Segment Information (Components of Revenue) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Summary of components of revenue
Revenue	$ 110,137	$ 113,375	$ 326,740	$ 338,175
MRI
Summary of components of revenue
Revenue	45,719	46,938	135,541	140,378
PET/CT
Summary of components of revenue
Revenue	33,542	36,089	101,089	110,495
Radiation Oncology
Summary of components of revenue
Revenue	23,550	19,717	68,218	57,931
Other Modalities And Other Revenue
Summary of components of revenue
Revenue	$ 7,326	$ 10,631	$ 21,892	$ 29,371