SEGMENT INFORMATION (Tables)

12 Months Ended

Dec. 31, 2016

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment

Eversource's segment information is as follows:

	For the Year Ended December 31, 2016
Eversource (Millions of Dollars)	Electric Distribution			Natural Gas Distribution			Electric Transmission			Other			Eliminations			Total
Operating Revenues	$	5,594.3		$	857.7		$	1,210.0		$	870.4		$	(893.3	)	$	7,639.1
Depreciation and Amortization	(504.7		)	(65.3		)	(185.8		)	(33.5		)	2.2			(787.1		)
Other Operating Expenses	(4,155.1		)	(628.9		)	(321.8		)	(778.1		)	891.8			(4,992.1		)
Operating Income	934.5			163.5			702.4			58.8			0.7			1,859.9
Interest Expense	(193.1		)	(41.3		)	(110.0		)	(63.5		)	6.9			(401.0		)
Interest Income	10.0			0.1			1.2			7.0			(7.3		)	11.0
Other Income, Net	4.8			0.6			18.3			1,020.1			(1,008.9		)	34.9
Income Tax (Expense)/Benefit	(288.8		)	(45.2		)	(238.2		)	16.5			0.7			(555.0		)
Net Income	467.4			77.7			373.7			1,038.9			(1,007.9		)	949.8
Net Income Attributable to Noncontrolling Interests	(4.6		)	—			(2.9		)	—			—			(7.5		)
Net Income Attributable to Common Shareholders	$	462.8		$	77.7		$	370.8		$	1,038.9		$	(1,007.9	)	$	942.3
Total Assets (as of)	$	18,367.5		$	3,303.8		$	8,751.5		$	14,493.1		$	(12,862.7	)	$	32,053.2
Cash Flows Used for Investments in Plant	$	812.6		$	255.3		$	801.0		$	108.0		$	—		$	1,976.9

	For the Year Ended December 31, 2015
Eversource (Millions of Dollars)	Electric Distribution			Natural Gas Distribution			Electric Transmission			Other			Eliminations			Total
Operating Revenues	$	5,903.6		$	995.5		$	1,069.1		$	863.6		$	(877.0	)	$	7,954.8
Depreciation and Amortization	(425.2		)	(70.5		)	(165.6		)	(29.0		)	2.1			(688.2		)
Other Operating Expenses	(4,470.2		)	(776.7		)	(314.9		)	(817.9		)	877.3			(5,502.4		)
Operating Income	1,008.2			148.3			588.6			16.7			2.4			1,764.2
Interest Expense	(186.3		)	(36.9		)	(105.8		)	(48.0		)	4.6			(372.4		)
Interest Income	5.7			0.1			1.6			4.4			(5.1		)	6.7
Other Income, Net	7.2			0.8			14.5			977.8			(972.8		)	27.5
Income Tax (Expense)/Benefit	(322.8		)	(40.1		)	(191.6		)	14.5			—			(540.0		)
Net Income	512.0			72.2			307.3			965.4			(970.9		)	886.0
Net Income Attributable to Noncontrolling Interests	(4.7		)	—			(2.8		)	—			—			(7.5		)
Net Income Attributable to Common Shareholders	$	507.3		$	72.2		$	304.5		$	965.4		$	(970.9	)	$	878.5
Total Assets (as of)	$	17,981.3		$	3,104.5		$	8,019.3		$	13,256.7		$	(11,781.5	)	$	30,580.3
Cash Flows Used for Investments in Plant	$	718.9		$	182.2		$	749.1		$	73.9		$	—		$	1,724.1

	For the Year Ended December 31, 2014
Eversource (Millions of Dollars)	Electric Distribution			Natural Gas Distribution			Electric Transmission			Other			Eliminations			Total
Operating Revenues	$	5,663.4		$	1,007.3		$	1,018.2		$	790.9		$	(737.9	)	$	7,741.9
Depreciation and Amortization	(384.6		)	(68.1		)	(150.5		)	(42.1		)	19.9			(625.4		)
Other Operating Expenses	(4,366.2		)	(786.7		)	(302.1		)	(748.0		)	719.3			(5,483.7		)
Operating Income	912.6			152.5			565.6			0.8			1.3			1,632.8
Interest Expense	(191.6		)	(34.0		)	(104.1		)	(36.6		)	4.2			(362.1		)
Interest Income	5.1			—			0.9			3.6			(3.6		)	6.0
Other Income, Net	10.7			0.2			10.3			916.0			(918.6		)	18.6
Income Tax (Expense)/Benefit	(269.7		)	(46.4		)	(174.5		)	22.3			—			(468.3		)
Net Income	467.1			72.3			298.2			906.1			(916.7		)	827.0
Net Income Attributable to Noncontrolling Interests	(4.7		)	—			(2.8		)	—			—			(7.5		)
Net Income Attributable to Common Shareholders	$	462.4		$	72.3		$	295.4		$	906.1		$	(916.7	)	$	819.5
Cash Flows Used for Investments in Plant	$	645.2		$	176.7		$	731.6		$	50.2		$	—		$	1,603.7