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.

No definition available.

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- Definition

Face amount or stated value per share of common stock.

+ 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(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

+ Details

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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- Details

Name:	dei_LegalEntityAxis=es_TheConnecticutLightAndPowerCompanyMember
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- Details

Name:	dei_LegalEntityAxis=es_NstarElectricCompanyMember
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- Details

Name:	dei_LegalEntityAxis=es_PublicServiceCompanyOfNewHampshirePSNHMember
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COMMON SHARES - Common Shares Authorized and Issued (Details) - $ / shares	Sep. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Mar. 31, 2020
Class of Stock [Line Items]
Par value (in dollars per share)	$ 5		$ 5	$ 5
Authorized (in shares)	380,000,000	380,000,000
Issued (in shares)	357,818,402	357,818,402
CL&P
Class of Stock [Line Items]
Par value (in dollars per share)	$ 10
Authorized (in shares)	24,500,000	24,500,000
Issued (in shares)	6,035,205	6,035,205
NSTAR Electric
Class of Stock [Line Items]
Par value (in dollars per share)	$ 1
Authorized (in shares)	100,000,000	100,000,000
Issued (in shares)	200	200
PSNH
Class of Stock [Line Items]
Par value (in dollars per share)	$ 1
Authorized (in shares)	100,000,000	100,000,000
Issued (in shares)	301	301