NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net (Loss)/Income	$ (434,700)	$ 1,412,400	$ 1,228,000
Other Comprehensive Income/(Loss), Net of Tax:
Other Comprehensive Income/(Loss), Net of Tax	5,700	2,900
Comprehensive (Loss)/Income Attributable to Common Shareholders	(436,556)	1,407,729	1,254,663
NSTAR Electric Company
Net (Loss)/Income	544,528	492,428	476,569
Other Comprehensive Income/(Loss), Net of Tax:
Changes in Funded Status of SERP Benefit Plan	(272)	(221)	(100)
Qualified Cash Flow Hedging Instruments	20	20	298
Changes in Unrealized Gains/(Losses) on Marketable Securities	12	(16)	(6)
Other Comprehensive Income/(Loss), Net of Tax	(240)	(217)	192
Comprehensive (Loss)/Income Attributable to Common Shareholders	$ 544,288	$ 492,211	$ 476,761