FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)

9 Months Ended

Sep. 30, 2016

Fair Value Disclosures [Abstract]

Fair Value, by Balance Sheet Grouping

Carrying amounts and estimated fair values are as follows:

	As of September 30, 2016				As of December 31, 2015
Eversource (Millions of Dollars)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Preferred Stock Not Subject to Mandatory Redemption	$	155.6	$	166.6	$	155.6	$	157.9
Long-Term Debt	9,609.0		10,454.8		9,034.5		9,425.9

	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 September 30, 2016:
Preferred Stock Not Subject to Mandatory Redemption	$	116.2	$	122.2	$	43.0	$	44.4	$	—	$	—	$	—	$	—
Long-Term Debt	2,765.4		3,216.8		2,078.0		2,338.8		1,071.8		1,142.9		566.7		616.9
As of December 31, 2015:
Preferred Stock Not Subject to Mandatory Redemption	$	116.2	$	114.9	$	43.0	$	43.0	$	—	$	—	$	—	$	—
Long-Term Debt	2,763.7		3,031.6		2,029.8		2,182.4		1,071.0		1,121.2		517.3		551.8