Business Combination, Consideration Transferred, Working Capital Adjustments

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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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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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The total amount of other operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The amount of regulated power revenues recognized during the period.

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Business Combinations - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended
	Feb. 04, 2019	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019
Business Acquisition [Line Items]
Electric operations		$ 311,157		$ 312,949
Decrease in other operations revenue		(44,908)		(39,397)
Depreciation and amortization		$ 55,873		49,856
South Central Generating
Business Acquisition [Line Items]
Consideration transferred	$ 962,200
Acquisition price	1,000,000
Working capital and other adjustments	$ 37,800
Pro forma net income				32,986
South Central Generating \| Fair Value Adjustments
Business Acquisition [Line Items]
Electric operations			$ 500
Decrease in other operations revenue			100
Depreciation and amortization			$ 200
South Central Generating \| Transaction-related expenses
Business Acquisition [Line Items]
Pro forma net income				$ 3,900