Contractual interest rate for funds borrowed, under the debt agreement.

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-Topic 210
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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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SHORT-TERM AND LONG-TERM DEBT - Summary of Long-Term Debt Issuance and Repayments (Details) - USD ($) $ in Thousands	1 Months Ended			3 Months Ended
	Apr. 30, 2021	Mar. 31, 2021	Feb. 28, 2021	Mar. 31, 2021	Mar. 31, 2020
Debt Instrument [Line Items]
Repayments				$ (572,000)	$ (220,253)
Senior Notes \| Eversource Parent 2.50% Series I Senior Notes \| Eversource Parent
Debt Instrument [Line Items]
Repayments			$ (450,000)
Interest rate, stated percentage			2.50%
Senior Notes \| Eversource Parent 2.55% Series S Senior Notes \| Eversource Parent
Debt Instrument [Line Items]
Issuances		$ 350,000
Interest rate, stated percentage		2.55%		2.55%
PSNH
Debt Instrument [Line Items]
Repayments				$ (122,000)	$ 0
PSNH \| Senior Notes \| 4.05% Series Q First Mortgage Bonds
Debt Instrument [Line Items]
Repayments		$ (122,000)
Interest rate, stated percentage		4.05%		4.05%
PSNH \| First Mortgage \| PSNH 3.20% Series R First Mortgage Bonds \| Subsequent Event
Debt Instrument [Line Items]
Interest rate, stated percentage	3.20%
Aquarion \| Senior Notes \| Aquarion Water Company of Connecticut 3.31% Senior Notes \| Subsequent Event
Debt Instrument [Line Items]
Issuances	$ 100,000
Interest rate, stated percentage	3.31%
Aquarion \| Senior Notes \| Aquarion Water Company of Connecticut 5.50% Notes \| Subsequent Event
Debt Instrument [Line Items]
Repayments	$ (40,000)
Interest rate, stated percentage	5.50%