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COMMITMENTS AND CONTINGENCIES - Guarantees and Obligations Narrative (Details) - USD ($) | Sep. 30, 2021 | Sep. 16, 2020
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Loss Contingencies [Line Items] |  |
Fair value of guarantees | $ 5,700,000 |
Letter of Credit | Eversource Investment LLC |  |
Loss Contingencies [Line Items] |  |
Maximum borrowing capacity |  | $ 25,000,000

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- Definition The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=124440162&loc=d3e12069-110248 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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