Restructuring Liability (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2003
Restructuring Cost and Reserve [Line Items]
Restructuring expense	$ 6,188	$ 39
Kendall Restructuring
Restructuring Cost and Reserve [Line Items]
Lease term (in years)			15 years
Discount rate, lease restructuring liability (as a percent)			10.00%
Restructuring expense	382	39
Fan Pier Move
Restructuring Cost and Reserve [Line Items]
Restructuring expense	$ 5,200