RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES- Rate Reduction Bonds, Principal and Interest Payments (Details) - PSNH $ in Millions	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
2023	$ 43.2
2024	43.2
2025	43.2
2026	43.2
2027	43.2
Thereafter	237.7
Total	$ 453.7

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