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	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019
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		345,858,402
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