Fair Value Measurements (Fair Value Of Notes Payable) (Details) - USD ($) $ in Millions		Dec. 31, 2022	Dec. 31, 2021
Carrying Value	[1]	$ 3,680.9	$ 3,170.4
Fixed Rate Notes Payable [Member]
Carrying Value		3,114.0	3,130.5
Estimated Fair Value		2,806.1	3,363.7
Floating Rate Notes Payable [Member]
Carrying Value	[2]	566.9	39.9
Estimated Fair Value	[2]	$ 566.8	$ 40.1

[1] Unamortized debt discounts, debt issuance costs, and fair market value adjustments of $18.0 million and $19.6 million are included in senior unsecured notes payable as of December 31, 2022 and 2021, respectively.

[2] Includes balances outstanding under our unsecured credit facility at December 31, 2022.