Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2015

Commitments and Contingencies Disclosure [Abstract]

Minimum rental commitments under non-cancelable leases

(In millions)	2016			2017			2018			2019			2020			Thereafter			Total
Minimum lease payments (1)	$	75.9		$	75.7		$	67.9		$	66.7		$	63.2		$	382.7		$	732.1
Less: income from subleases	(6.0		)	(6.0		)	(6.3		)	(6.3		)	(6.3		)	(28.9		)	(59.8		)
Net minimum lease payments	$	69.9		$	69.7		$	61.6		$	60.4		$	56.9		$	353.8		$	672.3

(1) As a result of our decision to relocate our corporate headquarters to Cambridge, Massachusetts, we vacated part of our Weston, Massachusetts facility in the fourth quarter of 2013. We incurred a charge of $27.2 million in connection with this move. This charge represented our remaining lease obligation for the vacated portion of our Weston, Massachusetts facility, net of sublease income expected to be received. The term of our sublease to the vacated portion of our Weston, Massachusetts facility started in January 2014 and will continue through the remaining term of our lease agreement.

Schedule of Future Minimum Lease Payments for Capital Leases [Table Text Block]

(In millions)	As of December 31, 2015
2016	$	2.0
2017	2.0
2018	16.7
2019	—
2020	—
Thereafter	—
Total	20.7
Less: interest	(0.9		)
Net present value of the future minimum lease payments	$	19.8