ACQUISITION OF ASSETS OF COLUMBIA GAS OF MASSACHUSETTS (Details) - Subsequent Event mile in Thousands, customer in Thousands, $ in Billions	Oct. 09, 2020 USD ($) customer community mile
Business Acquisition [Line Items]
Number of customers	300
CMA
Business Acquisition [Line Items]
Cash purchase price \| $	$ 1.1
CMA
Business Acquisition [Line Items]
Number of customers	330
Length of natural gas pipeline \| mile	5
Number of communities served \| community	60

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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