Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Taxes [Line Items]
Effective income tax rate	6.70%	(1.50%)	(1.80%)	(8.00%)
Corporate federal income tax rate	21.00%	21.00%	21.00%	21.00%
Decrease in income tax expense	$ (6,466)		$ 4,710
Regulatory Liabilities	$ 157,171		$ 157,171
State [Member]
Income Taxes [Line Items]
Effective income tax rate			2.50%	9.99%

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

+ References

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-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 405
-Section 25
-Paragraph 1
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Income Taxes [Line Items]

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No definition available.

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