Basis of Presentation Basis of Presentation (Details) - USD ($) $ in Millions	Jun. 30, 2019	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, right-of-use assets	$ 109.1
Operating lease liabilities	$ 111.1
ASC 842
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, right-of-use assets		$ 109.1
Operating lease liabilities		$ 110.4