Accounting Policies - New Accounting Pronouncements (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jan. 01, 2019
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 386.0
Operating lease liability	367.1
Operating lease liabilities, noncurrent	$ 246.3
Accounting Standards Update 2016-02
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating lease right-of-use assets		$ 378.8
Operating lease liability		378.8
Lease deposits		25.4
Operating lease liabilities, noncurrent		$ 25.4