Represents the amount of accounts receivable past due as of the specified date.

No definition available.

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- Definition

Represents the average number of days by which past due accounts receivable are overdue.

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No definition available.

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Represents the amount of proceeds received during the period from payments on accounts receivable that were overdue.

+ References

No definition available.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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- Definition

The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

+ References

No definition available.

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The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

The adjustment to expense previously capitalized costs of drilling exploratory wells when proved reserves are not found or when the entity obtains information that raises substantial doubt about the economic or operational viability of the project.

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Amount of cash inflow for proceeds from settlement of insurance claim, classified as operating activities. Excludes insurance settlement classified as investing activities.

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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue.

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Note 1 - General and Basis of Presentation 1 (Details Textual) $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended		12 Months Ended
	Apr. 30, 2020 USD ($)	Apr. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Exploration Abandonment and Impairment Expense			$ 0	$ 0
Cash, FDIC Insured Amount			14,400		$ 12,900
Cash, Uninsured Amount			228,800		84,800
Accounts Receivable, after Allowance for Credit Loss, Current, Total			168,924		$ 154,525
Product [Member]
Revenue, Remaining Performance Obligation, Amount			$ 96,500
Revenue, Remaining Performance Obligation, Percentage			100.00%
Kenya Power and Lighting Co LTD [Member]
Accounts Receivable, Past Due			$ 38,600
Accounts Receivable, Past Due, Average Number of Days Overdue			61
Kenya Power and Lighting Co LTD [Member] \| Subsequent Event [Member]
Proceeds, Overdue Accounts Receivable	$ 8,000
ENNE [Member]
Accounts Receivable, Past Due			$ 20,100
Accounts Receivable, Credit Loss Expense (Reversal)			$ 0
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Primary Customers [Member]
Concentration Risk, Percentage			50.00%		58.00%
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Sierra Pacific Power Company And Nevada Power Company [Member]
Concentration Risk, Percentage			19.20%	18.30%
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Southern California Public Power Authority [Member]
Concentration Risk, Percentage			18.70%	19.40%
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Kenya Power and Lighting Co LTD [Member]
Concentration Risk, Percentage			15.40%	15.30%
Non-US [Member]
Accounts Receivable, after Allowance for Credit Loss, Current, Total			$ 135,100		$ 118,800
Electricity Segment [Member] \| Puna Geothermal Power Plant [Member]
Proceeds from Insurance Settlement, Operating Activities		$ 3,000
Electricity Segment [Member] \| Puna Geothermal Power Plant [Member] \| Cost of Sales [Member]
Proceeds from Insurance Settlement, Operating Activities			$ 4,900