Accounting Pronouncements - Recently Adopted (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Lease, Liability	$ 522.2
Operating Lease, Right-of-Use Asset	$ 522.4		$ 0.0
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Lease, Liability		$ 500.0
Operating Lease, Right-of-Use Asset		$ 500.0