SHORT-TERM DEBT (Tables)

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

Schedule of Borrowings Outstanding

The amount of borrowings outstanding and available under the commercial paper programs were as follows:

	Borrowings Outstanding  as of December 31,				Available Borrowing Capacity as of December 31,				Weighted-Average Interest Rate as of December 31,
(Millions of Dollars)	2023		2022		2023		2022		2023		2022
Eversource Parent Commercial Paper Program	$	1,771.9	$	1,442.2	$	228.1	$	557.8	5.60	%	4.63	%
NSTAR Electric Commercial Paper Program	365.8		—		284.2		650.0		5.40	%	—	%

Details of long-term debt outstanding are as follows:

CL&P (Millions of Dollars)			As of December 31,
	Interest Rate		2023		2022
First Mortgage Bonds:
1994 Series D due 2024	7.875	%	$	139.8	$	139.8
2004 Series B due 2034	5.750	%	130.0		130.0
2005 Series B due 2035	5.625	%	100.0		100.0
2006 Series A due 2036	6.350	%	250.0		250.0
2007 Series B due 2037	5.750	%	150.0		150.0
2007 Series D due 2037	6.375	%	100.0		100.0
2013 Series A due 2023	2.500	%	—		400.0
2014 Series A due 2044	4.300	%	475.0		475.0
2015 Series A due 2045	4.150	%	350.0		350.0
2017 Series A due 2027	3.200	%	500.0		500.0
2018 Series A due 2048	4.000	%	800.0		800.0
2020 Series A due 2025	0.750	%	400.0		400.0
2021 Series A due 2031	2.050	%	425.0		425.0
2023 Series A due 2053	5.250	%	500.0		—
2023 Series B due 2033	4.900	%	300.0		—
Total First Mortgage Bonds			4,619.8		4,219.8
Less Amounts due Within One Year			(139.8)		(400.0)
Current Portion Classified as Long-Term Debt (1)			139.8		400.0
Commercial Paper Classified as Long-Term Debt (See Note 8, Short-Term Debt)			207.3		—
Unamortized Premiums and Discounts, Net			18.0		21.5
Unamortized Debt Issuance Costs			(30.7)		(24.8)
CL&P Long-Term Debt			$	4,814.4	$	4,216.5

NSTAR Electric (Millions of Dollars)			As of December 31,
	Interest Rate		2023		2022
Debentures:
2006 Debentures due 2036	5.750	%	$	200.0	$	200.0
2010 Debentures due 2040	5.500	%	300.0		300.0
2014 Debentures due 2044	4.400	%	300.0		300.0
2015 Debentures due 2025	3.250	%	250.0		250.0
2016 Debentures due 2026	2.700	%	250.0		250.0
2017 Debentures due 2027	3.200	%	700.0		700.0
2019 Debentures due 2029	3.250	%	400.0		400.0
2020 Debentures due 2030	3.950	%	400.0		400.0
2021 Debentures due 2051	3.100	%	300.0		300.0
2021 Debentures due 2031	1.950	%	300.0		300.0
2022 Debentures due 2052	4.550	%	450.0		450.0
2022 Debentures due 2052	4.950	%	400.0		400.0
2023 Debentures due 2028	5.600	%	150.0		—
Total Debentures			4,400.0		4,250.0
Notes:
2004 Senior Notes Series B due 2034	5.900	%	50.0		50.0
2007 Senior Notes Series D due 2037	6.700	%	40.0		40.0
2013 Senior Notes Series G due 2023	3.880	%	—		80.0
2016 Senior Notes Series H due 2026	2.750	%	50.0		50.0
Total Notes			140.0		220.0
Less Amounts due Within One Year			—		(80.0)
Unamortized Premiums and Discounts, Net			(14.0)		(14.8)
Unamortized Debt Issuance Costs			(29.1)		(30.1)
NSTAR Electric Long-Term Debt			$	4,496.9	$	4,345.1

PSNH (Millions of Dollars)			As of December 31,
	Interest Rate		2023		2022
First Mortgage Bonds:
2005 Series M due 2035	5.600	%	$	50.0	$	50.0
2013 Series S due 2023	3.500	%	—		325.0
2019 Series T due 2049	3.600	%	300.0		300.0
2020 Series U due 2050	2.400	%	150.0		150.0
2021 Series V due 2031	2.200	%	350.0		350.0
2023 Series W due 2053	5.150	%	300.0		—
2023 Series X due 2033	5.350	%	300.0		—
Total First Mortgage Bonds			1,450.0		1,175.0
Less Amounts due Within One Year			—		(325.0)
Current Portion Classified as Long-Term Debt (1)			—		295.3
Unamortized Premiums and Discounts, Net			(4.9)		(2.5)
Unamortized Debt Issuance Costs			(13.5)		(7.9)
PSNH Long-Term Debt			$	1,431.6	$	1,134.9

OTHER (Millions of Dollars)					As of December 31,
	Interest Rate				2023		2022
Eversource Parent - Senior Notes due 2024 - 2050	0.800	%	-	5.950%	$	10,300.0	$	8,150.0
Yankee Gas - First Mortgage Bonds due 2024 - 2051	1.380	%	-	5.510%	1,015.0		845.0
NSTAR Gas - First Mortgage Bonds due 2025 - 2051	2.250	%	-	7.110%	705.0		705.0
EGMA - First Mortgage Bonds due 2028 - 2052	2.110	%	-	5.730%	708.0		650.0
Aquarion - Senior Notes due 2024	4.000%				360.0		360.0
Aquarion - Unsecured Notes due 2028 - 2052	3.000	%	-	6.430%	527.0		464.7
Aquarion - Secured Debt due 2027 - 2044	1.550	%	-	9.290%	39.0		34.4
Pre-1983 Spent Nuclear Fuel Obligation (CYAPC)					12.5		11.9
Fair Value Adjustment (2)					19.3		26.2
Less Fair Value Adjustment - Current Portion (2)					(5.5)		(7.0)
Less Amounts due in One Year					(1,810.2)		(1,203.4)
Current Portion Classified as Long-Term Debt (1)					990.9		—
Unamortized Premiums and Discounts, Net					49.7		40.1
Unamortized Debt Issuance Costs					(65.0)		(49.4)
Total Other Long-Term Debt					$	12,845.7	$	10,027.5
Total Eversource Long-Term Debt					$	23,588.6	$	19,724.0

(1)     As a result of the CL&P and Eversource parent long-term debt issuances in January 2024, $139.8 million and $990.9 million, respectively, of current portion of long-term debt were reclassified as Long-Term Debt on CL&P’s and Eversource parent’s balance sheets as of December 31, 2023. As a result of the CL&P and PSNH long-term debt issuances in January 2023, $400 million and $295.3 million, respectively, of current portion of long-term debt were reclassified as Long-Term Debt on CL&P’s and PSNH’s balance sheets as of December 31, 2022.

(2)     The fair value adjustment amount is the purchase price adjustments, net of amortization, required to record long-term debt at fair value on the dates of the 2012 merger with NSTAR and the 2017 acquisition of Aquarion.