General Business (Narrative) (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Revenue, Major Customer [Line Items]
DD&A	$ 10,627,000	$ 11,738,000
Revenue	62,538,000	$ 89,313,000
Right-of-use asset	723,000		$ 800,000
Operating lease liabilities	$ 723,000
Sunrise Energy [Member]
Revenue, Major Customer [Line Items]
Equity method investment ownership percentage	50.00%

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of lessee's right to use underlying asset under operating lease.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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