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PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION - Narrative (Details) $ in Millions | Sep. 30, 2021 USD ($)
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Defined Benefit Plan Disclosure [Line Items] |
Expected pension plan contributions | $ 180
CL&P |
Defined Benefit Plan Disclosure [Line Items] |
Expected pension plan contributions | 99
NSTAR Electric |
Defined Benefit Plan Disclosure [Line Items] |
Expected pension plan contributions | $ 30

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- Definition Amount of contribution expected to be received by defined benefit plan from employer in remainder of current fiscal year. Excludes contribution previously paid by employer in current fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921 + Details
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