Fair Value Disclosure (Details 3) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Carrying Amount [Member]
Assets
Investment Funds	$ 0.6		$ 0.6
Loans	5.7		6.2
Liabilities
Recourse fixed rate debt	3,857.0		3,858.5
Recourse floating rate debt	418.6		417.8
Estimate of Fair Value Measurement [Member]
Assets
Investment Funds	1.1		1.2
Loans	5.7		6.2
Liabilities
Recourse fixed rate debt	3,902.9		3,852.6
Recourse floating rate debt	417.6		$ 412.2
Not Designated as Hedging Instrument [Member] | Other Expense [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net	$ 4.8	$ 1.3