Rate Matters and Regulation Rate Matters and Regulation (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 5.2
Estimated Refund to SPP	13.0
Investment in Grid Enhancement	800.0
Impact to Company [Member]
Estimated Refund to SPP	5.0
Customer Impact [Member]
Estimated Refund to SPP	$ 8.0