Discontinued Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jun. 30, 2020	Dec. 31, 2019
Disposal Group, Including Discontinued Operation, Classified Balance Sheet Disclosures [Abstract]
Discontinued operations - total assets	$ 15,300	$ 14,600		$ 15,100
Discontinued Operation, Income Statement Disclosures [Abstract]
Loss from discontinued operations, net of tax	$ (778)	$ (217)
Loss from discontinued operations per share of common stock
Basic (in dollars per share)	$ (0.02)	$ (0.01)
Diluted (in dollars per share)	$ (0.02)	$ (0.01)
Gill Ranch [Member] | Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Disposal Group, Including Discontinued Operation, Classified Balance Sheet Disclosures [Abstract]
Accounts receivable	$ 514	$ 1,277		333
Inventories	689	627		695
Other current assets	386	337		457
Property, plant, and equipment	13,349	12,033		13,291
Less: Accumulated depreciation	7	7		7
Operating lease right of use asset	118	118		118
Other non-current assets	247	247		247
Discontinued operations - total assets	15,296	14,632		15,134
Accounts payable	717	1,102		1,250
Other current liabilities	553	359		848
Operating lease liabilities	110	111		116
Other non-current liabilities	11,421	11,710		11,495
Total discontinued operations liabilities	12,801	13,282		$ 13,709
Gill Ranch [Member] | Discontinued Operations, Held-for-sale [Member]
Discontinued Operation, Income Statement Disclosures [Abstract]
Revenues	908	1,721
Operations and maintenance	1,580	1,613
General taxes	47	59
Depreciation and amortization	106	106
Other expenses and interest	231	237
Total expenses	1,964	2,015
Loss from discontinued operations before income tax	(1,056)	(294)
Income tax benefit	(278)	(77)
Loss from discontinued operations, net of tax	$ (778)	$ (217)
Loss from discontinued operations per share of common stock
Basic (in dollars per share)	$ (0.02)	$ (0.01)
Diluted (in dollars per share)	$ (0.02)	$ (0.01)
Gill Ranch [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percent ownership	75.00%
Pacific Gas and Electric Company [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percent ownership	25.00%
Forecast [Member] | Minimum [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses			$ 25,000
Forecast [Member] | Maximum [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses			$ 26,500