Investments Low Income Housing Tax Credits (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Investments, All Other Investments [Abstract]
Low Income Housing Tax Credits	$ 9.5	$ 10.4	$ 28.3	$ 31.1
Amortization of Low Income Housing Investments	(6.1)	(7.1)	(19.0)	(21.1)
Tax Benefits from Low Income Housing Investments	$ 3.4	$ 3.3	$ 9.3	$ 10.0