Investments in Unconsolidated Affiliates (Tables)

12 Months Ended

Dec. 31, 2016

Equity Method Investments and Joint Ventures [Abstract]

Investments in Equity Method Unconsolidated Affiliates

The table below outlines Duke Energy's ownership interests in natural gas pipeline companies and natural gas storage facilities. See Notes 4 and 17 for more information.

			Investment Amount (in millions)
	Ownership		December 31,		December 31,
Entity Name	Interest		2016		2015
Pipeline Investments
Atlantic Coast Pipeline, LLC	47	%	$	265	$	52
Sabal Trail Transmission, LLC	7.5	%	140		61
Constitution Pipeline, LLC	24	%	82		—
Cardinal Pipeline Company, LLC	21.49	%	16		—
Storage Facilities
Pine Needle LNG Company, LLC	45	%	16		—
Hardy Storage Company, LLC	50	%	47		—
Total Investments			$	566	$	113

The following table presents Duke Energy’s investments in unconsolidated affiliates accounted for under the equity method, as well as the respective equity in earnings, by segment.

	Years Ended December 31,
	2016					2015					2014
			Equity in					Equity in			Equity in
(in millions)	Investments		earnings			Investments		earnings			earnings
Electric Utilities and Infrastructure	$	93	$	5		$	57	$	(2	)	$	(1	)
Gas Utilities and Infrastructure	566		19			113		1			—
Commercial Renewables	185		(82		)	265		(6		)	8
Other	81		43			64		76			123
Total	$	925	$	(15	)	$	499	$	69		$	130