Fair Value Of Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Commitments Investments In Affiliated And Unaffiliated Partnerships	$ 11.4	$ 11.4	$ 11.5
General and limited partnership interests in investment partnerships	36.6	36.6	42.1
Direct investments in private equity companies held by private equity funds	18.0	18.0	$ 21.2
Fair Value Level One To Level Two Transfers Amount		5.6
Transfers, Out of Level 3, Assets	$ 0.0	$ 5.9
Stated interest rate	5.375%	5.375%
Maturity date		Dec. 31, 2022