Investments in Non-Controlled Entities (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments Unamortized Excess Investment Net	$ 59.7	$ 61.3

Equity Method Investments Unamortized Excess Investment, Net

No definition available.

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