Operating Revenues - Other Non-Utility Operating Revenues (Details) - Revenues from contracts with customers - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of Operating Revenues
Revenues from contracts with customers	$ 9,568.1	$ 8,235.7	$ 7,169.3
Other non-utility revenues
Disaggregation of Operating Revenues
Revenues from contracts with customers	143.2	101.5	76.3
Other non-utility revenues | We Power revenues
Disaggregation of Operating Revenues
Revenues from contracts with customers	23.4	23.3	22.9
Other non-utility revenues | Other
Disaggregation of Operating Revenues
Revenues from contracts with customers	0.1	0.1	1.7
Transferred over time | Other non-utility revenues | Wind generation revenues
Disaggregation of Operating Revenues
Revenues from contracts with customers	101.0	60.3	34.6
Transferred over time | Other non-utility revenues | Appliance service repairs
Disaggregation of Operating Revenues
Revenues from contracts with customers	$ 18.7	$ 17.8	$ 17.1