Restructuring Liabilities (Details)	12 Months Ended	3 Months Ended
	Dec. 31, 2003	Mar. 31, 2015 lease sqft	Dec. 31, 2011 sqft
Restructuring Cost and Reserve [Line Items]
Area of real estate property (in square feet)			1,100,000
Kendall Restructuring
Restructuring Cost and Reserve [Line Items]
Lease term (in years)	15 years
Restructuring and related activities, leased office space, maximum percentage used - not more than	50.00%
Fan Pier Move Restructuring
Restructuring Cost and Reserve [Line Items]
Number of leases terminated		2
Area of real estate property (in square feet)		120,000
Discount rate related to leases (percent)		9.00%