Number Of Counties In Which Entity Operates

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- Definition

Number Of Sale-Leasback Projects

+ References

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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

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Amount of lessee's right to use underlying asset under operating lease.

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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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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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Thousands			3 Months Ended
	Jul. 31, 2020 USD ($)	Feb. 18, 2020 USD ($)	Jun. 30, 2021 USD ($) county project	Mar. 31, 2020 USD ($)	Jun. 09, 2021	Aug. 12, 2020	Aug. 07, 2020	Aug. 06, 2020
Public Utilities, General Disclosures [Line Items]
Number of sale-leaseback projects \| project			10
Valuation allowance			$ 14,200
Reserve from prior period tax positions			13,900
Operating lease, liability			6,600
ROU assets			$ 6,600
Term of operating lease			35 years
EnerConnex, LLC
Public Utilities, General Disclosures [Line Items]
Remaining equity interest acquired (as a percent)							75.00%
Equity interest in acquiree previously held (as a percent)								25.00%
Disposed of by sale
Public Utilities, General Disclosures [Line Items]
Consideration received on sales of projects				$ 7,200
Disposed of by sale \| MTF and ACB
Public Utilities, General Disclosures [Line Items]
Consideration received on sales of projects		$ 97,000
Disposed of by sale \| ELK Utility Operations
Public Utilities, General Disclosures [Line Items]
Consideration received on sales of projects	$ 15,600
ETG Utility Operations
Public Utilities, General Disclosures [Line Items]
Number of counties in which entity operates \| county			7
SJG
Public Utilities, General Disclosures [Line Items]
Number of counties in which entity operates \| county			7
Marina \| Catamaran
Public Utilities, General Disclosures [Line Items]
Ownership by parent (as a percent)					92.00%
Marina \| Annadale \| Annadale
Public Utilities, General Disclosures [Line Items]
Ownership by parent (as a percent)						93.00%
Marina \| Annadale \| Bronx Midco LLC
Public Utilities, General Disclosures [Line Items]
Ownership by parent (as a percent)						92.00%
Catamaran \| Bronx Midco LLC
Public Utilities, General Disclosures [Line Items]
Ownership by parent (as a percent)					99.00%