Summary of Significant Accounting Policies - Leases (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts payable, accrued expenses and other liabilities	$ 354.9		$ 442.2
Lease right-of-use assets, net	$ 203.8		$ 0.0
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts payable, accrued expenses and other liabilities		$ (65.2)
Lease right-of-use assets, net		$ 65.2