Commitments and Contingencies - Future Minimum Payments Under Non-Cancelable Leases, Sublease Commitments and Related Payments (Details) $ in Millions	Dec. 31, 2015 USD ($)
Payments [Abstract]
2016	$ 137.9
2017	139.0
2018	130.0
2019	124.1
2020	102.5
2021 and thereafter	740.5
Total future minimum payments	1,374.0
Sublease Receipts [Abstract]
2016	43.7
2017	42.5
2018	41.8
2019	41.2
2020	24.7
2021 and thereafter	102.1
Total future minimum payments receivable	296.0
Net Payments [Abstract]
2016	94.2
2017	96.5
2018	88.2
2019	82.9
2020	77.8
2021 and thereafter	638.4
Total future net minimum payments	$ 1,078.0