Commitments And Contingencies (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Loss Contingencies [Line Items]
Regulatory liabilities	$ 66,336	$ 51,715
Provision for Rate Refunds [Member]
Loss Contingencies [Line Items]
Regulatory liabilities	8,490	3,565
Provision for Rate Refunds [Member] | Natural Gas [Member]
Loss Contingencies [Line Items]
Regulatory liabilities	3,600
Provision for Rate Refunds [Member] | Electricity [Member]
Loss Contingencies [Line Items]
Regulatory liabilities	$ 4,900	$ 3,600