Fair Value Of Assets And Liabilities (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (loss) on derivative	$ 8.2	$ 2.5
Fair Value Inputs, Discount Rate	3.88%
Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets under Management, Assumed Growth Rate	0.69%
Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets under Management, Assumed Growth Rate	4.40%
Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets under Management, Assumed Growth Rate	2.48%
Foreign Exchange Option [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Put option contracts, purchases	$ 4.2	$ 7.0