FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)

3 Months Ended

Mar. 31, 2017

Fair Value Disclosures [Abstract]

Fair Value, by Balance Sheet Grouping

Carrying amounts and estimated fair values are as follows:

	As of March 31, 2017				As of December 31, 2016
Eversource (Millions of Dollars)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Preferred Stock Not Subject to Mandatory Redemption	$	155.6	$	156.6	$	155.6	$	158.3
Long-Term Debt	10,041.8		10,428.0		9,603.2		9,980.5

	CL&P				NSTAR Electric				PSNH				WMECO
(Millions of Dollars)	Carrying Amount		Fair Value		Carrying Amount		Fair Value		Carrying Amount		Fair Value		Carrying Amount		Fair Value
As of March 31, 2017:
Preferred Stock Not Subject to Mandatory Redemption	$	116.2	$	113.5	$	43.0	$	43.1	$	—	$	—	$	—	$	—
Long-Term Debt	2,913.2		3,179.5		2,078.5		2,202.9		1,072.3		1,115.2		566.4		596.8
As of December 31, 2016:
Preferred Stock Not Subject to Mandatory Redemption	$	116.2	$	114.7	$	43.0	$	43.6	$	—	$	—	$	—	$	—
Long-Term Debt	2,766.0		3,049.6		2,078.1		2,201.6		1,072.0		1,109.7		566.5		589.0