Fair Value Measurements (Fair Value Of Notes Payable) (Details) - USD ($) $ in Millions		Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Carrying Value	[1]	$ 3,688.0	$ 3,170.4
Fixed rate notes payable
Carrying Value		3,463.1	3,130.5
Estimated Fair Value		3,125.0	3,363.7
Floating rate notes payable (1)
Carrying Value		225.0	39.9	$ 39.9
Estimated Fair Value		$ 222.6	$ 40.1

[1] Unamortized debt discounts, debt issuance costs and fair market value adjustments of $18.9 million and $19.6 million are included in notes payable as of September 30, 2022 and December 31, 2021, respectively.