Business Segments

3 Months Ended

Mar. 31, 2016

Segment Reporting [Abstract]

Business Segments

BUSINESS SEGMENTS

Duke Energy evaluates segment performance based on segment income. Segment income is defined as income from continuing operations net of income attributable to noncontrolling interests. Segment income, as discussed below, includes intercompany revenues and expenses that are eliminated in the Condensed Consolidated Financial Statements. Certain governance costs are allocated to each segment. In addition, direct interest expense and income taxes are included in segment income.

During the first quarter of 2016, the Duke Energy chief operating decision-maker began to evaluate interim period segment performance based on financial information that includes the impact of income tax levelization within segment income. This represents a change from the previous measure, where the interim period impacts of income tax levelization were included within Other, and therefore excluded from segment income. As a result, prior period segment results presented have been recast to conform to this change.

Operating segments are determined based on information used by the chief operating decision-maker in deciding how to allocate resources and evaluate the performance of the business.

Products and services are sold between affiliate companies and reportable segments of Duke Energy at cost. Segment assets as presented in the tables that follow exclude all intercompany assets.

DUKE ENERGY

Duke Energy has the following reportable operating segments: Regulated Utilities, International Energy and Commercial Portfolio.

RegulatedUtilities conducts electric and natural gas operations that are substantially all regulated and, accordingly, qualify for regulatory accounting treatment. These operations are primarily conducted through the Subsidiary Registrants and are subject to the rules and regulations of the FERC, NRC, NCUC, PSCSC, FPSC, PUCO, IURC and KPSC.

International Energy principally operates and manages power generation facilities and engages in sales and marketing of electric power, natural gas and natural gas liquids outside the U.S. Its activities principally target power generation in Latin America. Additionally, International Energy owns a 25 percent interest in NMC, a large regional producer of methyl tertiary butyl ether (MTBE) located in Saudi Arabia. The investment in NMC is accounted for under the equity method of accounting. In February 2016, Duke Energy announced it had initiated a process to potentially divest its International Energy business segment, excluding the investment in NMC. See Note 2 for further information.

Commercial Portfolio builds, develops and operates wind and solar renewable generation and energy transmission projects throughout the U.S. For periods subsequent to the sale of the Disposal Group, beginning in the second quarter of 2015, certain immaterial results of operations and related assets previously presented in the Commercial Portfolio segment are presented in Regulated Utilities and Other.

Theremainder of Duke Energy’s operations is presented as Other, which is primarily comprised of unallocated corporate interest expense, unallocated corporate costs, contributions to the Duke Energy Foundation and the operations of Duke Energy’s wholly owned captive insurance subsidiary, Bison Insurance Company Limited (Bison).

	Three Months Ended March 31, 2016
							Total
	Regulated		International		Commercial		Reportable
(in millions)	Utilities		Energy		Portfolio		Segments		Other			Eliminations			Consolidated
Unaffiliated revenues	$	5,250	$	246	$	114	$	5,610	$	12		$	—		$	5,622
Intersegment revenues	9		—		—		9		17			(26		)	—
Total revenues	$	5,259	$	246	$	114	$	5,619	$	29		$	(26	)	$	5,622
Segment income (loss)(a)	$	695	$	123	$	27	$	845	$	(154	)	$	—		$	691
Add back noncontrolling interests															5
Income from discontinued operations, net of tax															3
Net income															$	699
Segment assets	$	111,838	$	3,247	$	4,183	$	119,268	$	2,263		$	178		$	121,709

(a)    Other includes $74 million of after-tax costs to achieve mergers and a $12 million after-tax charge related to cost savings initiatives.

	Three Months Ended March 31, 2015
							Total
	Regulated		International		Commercial		Reportable
(in millions)	Utilities		Energy		Portfolio		Segments		Other			Eliminations			Consolidated
Unaffiliated revenues	$	5,713	$	273	$	73	$	6,059	$	6		$	—		$	6,065
Intersegment revenues	10		—		—		10		21			(31		)	—
Total revenues	$	5,723	$	273	$	73	$	6,069	$	27		$	(31	)	$	6,065
Segment income (loss)(a)	$	774	$	36	$	7	$	817	$	(43	)	$	(1	)	$	773
Add back noncontrolling interests															3
Income from discontinued operations, net of tax															91
Net income															$	867
Segment assets	$	106,642	$	4,892	$	6,202	$	117,736	$	4,230		$	176		$	122,142

(a)     Other includes after-tax costs to achieve the 2012 Progress Energy merger of $13 million.

DUKE ENERGY CAROLINAS, PROGRESS ENERGY, DUKE ENERGY PROGRESS, DUKE ENERGY FLORIDA, DUKE ENERGY OHIO AND DUKE ENERGY INDIANA

The Subsidiary Registrants each have one reportable operating segment, Regulated Utilities, which generates, transmits, distributes and sells electricity, and for Duke Energy Ohio, also transports and sells natural gas. The remainder of each company’s operations is classified as Other. While not considered a reportable segment for any of these companies, Other consists of certain unallocated corporate costs. Other for Progress Energy also includes interest expense on corporate debt instruments of $56 million and $60 million for the three months ended March 31, 2016 and 2015, respectively. Other for Duke Energy Ohio also includes amounts related to Duke Energy Ohio's contractual arrangement to buy power from Ohio Valley Electric Corporations (OVEC's) power plants. The following table summarizes the net loss for Other for each of these entities.

	Three Months Ended
	March 31,
(in millions)	2016			2015
Duke Energy Carolinas	$	(17	)	$	(8	)
Progress Energy	(49		)	(42		)
Duke Energy Progress	(8		)	(4		)
Duke Energy Florida	(4		)	(3		)
Duke Energy Ohio	(9		)	(2		)
Duke Energy Indiana	(2		)	(2		)

The assets at Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida, Duke Energy Ohio and Duke Energy Indiana are substantially all included within the Regulated Utilities segment at March 31, 2016.

Duke Energy Ohio

Duke Energy Ohio had two reportable operating segments, Regulated Utilities and Commercial Portfolio, prior to the sale of the nonregulated Midwest generation business. As a result of the sale discussed in Note 2, Commercial Portfolio no longer qualifies as a Duke Energy Ohio reportable operating segment. Therefore, for periods subsequent to the sale, beginning in the second quarter of 2015, all of the remaining assets and related results of operations previously presented in Commercial Portfolio are presented in Regulated Utilities and Other. The following table summarizes segment information prior to the sale of the nonregulated Midwest generation business.

	Three Months Ended March 31, 2015
						Total
	Regulated		Commercial			Reportable
(in millions)	Utilities		Portfolio			Segments		Other			Eliminations			Consolidated
Total revenues	$	572	$	14		$	586	$	—		$	—		$	586
Segment income (loss)	$	70	$	(9	)	$	61	$	(2	)	$	—		$	59
Income from discontinued operations, net of tax														90
Net income														$	149
Segment assets	$	6,782	$	2,984		$	9,766	$	43		$	(13	)	$	9,796