Recent Accounting Pronouncements (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Present value of lease liabilities	$ 509.7
Operating lease right-of-use asset	$ 460.4
ASU 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Present value of lease liabilities		$ 530.0
Operating lease right-of-use asset		$ 480.0