Summary of Significant Accounting Policies (Details) (USD $) In Millions, unless otherwise specified			3 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Basel, Switzerland	Dec. 31, 2013 Basel, Switzerland	Mar. 31, 2013 Property and equipment Basel, Switzerland	Dec. 31, 2011 Property and equipment Vienna, Virginia
Principles of Consolidation
Equity method investments ownership, low end of range (as a percent)	20.00%
Equity method investments ownership, high end of range (as a percent)	50.00%
Cost method investments ownership, maximum (as a percent)	20.00%
Inventory
Finished goods	$ 33.5	$ 30.3
Supplies	18.9	18.0
Prepaid Expenses and Other Current Assets
Amounts receivable from customers in connection with billed and unbilled investigator fees, volunteer payments and other out-of-pocket pass-through costs	103.5	88.9
Long-lived assets held for sale					8.3	27.0
Impairment of long-lived assets held for sale			$ 2.5	$ 2.3