Business Segments (Tables)

12 Months Ended

Dec. 31, 2015

Segment Reporting Information [Line Items]

Business Segment Data

The following table summarizes the net loss for Other for each of these entities.

	Years Ended December 31,
(in millions)	2015			2014			2013
Duke Energy Carolinas	$	(95	)	$	(79	)	$	(97	)
Progress Energy	(159		)	(190		)	(241		)
Duke Energy Progress	(32		)	(31		)	(46		)
Duke Energy Florida	(16		)	(19		)	(24		)
Duke Energy Indiana	(10		)	(11		)	(16		)

	Year Ended December 31, 2015
									Total
	Regulated			International		Commercial			Reportable
(in millions)	Utilities			Energy		Portfolio			Segments		Other			Eliminations			Total
Unaffiliated Revenues	$	22,024		$	1,088	$	301		$	23,413	$	46		$	—		$	23,459
Intersegment Revenues	38			—		—			38		77			(115		)	—
Total Revenues	$	22,062		$	1,088	$	301		$	23,451	$	123		$	(115	)	$	23,459
Interest Expense	$	1,097		$	85	$	44		$	1,226	$	393		$	(6	)	$	1,613
Depreciation and amortization	2,814			92		104			3,010		134			—			3,144
Equity in earnings of unconsolidated affiliates	(4		)	74		(3		)	67		2			—			69
Income tax expense (benefit)	1,647			74		(92		)	1,629		(303		)	—			1,326
Segment income (loss)(a)(b)(c)(d)	2,893			225		4			3,122		(322		)	(4		)	2,796
Add back noncontrolling interest component																	15
Income from discontinued operations, net of tax(e)																	20
Net income																	$	2,831
Capital investments expenditures and acquisitions	$	6,974		$	45	$	1,131		$	8,150	$	213		$	—		$	8,363
Segment Assets	111,562			3,271		4,010			118,843		2,125			188			121,156

(a) Regulated Utilities includes an after-tax charge of $58 million related to the Edwardsport settlement. Refer to Note 4 for further information.

(b) Commercial Portfolio includes state tax expense of $41 million, resulting from changes to state apportionment factors due to the sale of the Disposal Group, that does not qualify for discontinued operations. Refer to Note 2 for further information related to the sale.

(c)    Other includes $60 million of after-tax costs to achieve mergers.

(d) Other includes an after-tax charge of $77 million related to cost savings initiatives. Refer to Note 19 for further information related to the cost savings initiatives.

(e) Includes after-tax impact of $53 million for the settlement agreement reached in a lawsuit related to the Disposal Group. Refer to Note 5 for further information related to the lawsuit.

	Year Ended December 31, 2014
									Total
	Regulated			International		Commercial			Reportable
(in millions)	Utilities			Energy		Portfolio			Segments		Other			Eliminations			Total
Unaffiliated Revenues	$	22,228		$	1,417	$	255		$	23,900	$	25		$	—		$	23,925
Intersegment Revenues	43			—		—			43		80			(123		)	—
Total Revenues	$	22,271		$	1,417	$	255		$	23,943	$	105		$	(123	)	$	23,925
Interest Expense	$	1,093		$	93	$	58		$	1,244	$	400		$	(22	)	$	1,622
Depreciation and amortization	2,759			97		92			2,948		118			—			3,066
Equity in earnings of unconsolidated affiliates	(3		)	120		10			127		3			—			130
Income tax expense (benefit)(a)	1,628			449		(171		)	1,906		(237		)	—			1,669
Segment income (loss)(b)(c)(d)	2,795			55		(55		)	2,795		(334		)	(10		)	2,451
Add back noncontrolling interest component																	14
Loss from discontinued operations, net of tax																	(576		)
Net income																	$	1,889
Capital investments expenditures and acquisitions	$	4,744		$	67	$	555		$	5,366	$	162		$	—		$	5,528
Segment Assets	106,574			5,093		6,278			117,945		2,423			189			120,557

(a) International Energy includes a tax adjustment of $373 million related to deferred tax impact resulting from the decision to repatriate all cumulative historical undistributed foreign earnings. See Note 22 for additional information.

(b) Commercial Portfolio recorded a $94 million pretax impairment charge related to OVEC.

(c) Other includes costs to achieve mergers.

(d) Regulated Utilities includes an increase in the litigation reserve related to the criminal investigation of the Dan River coal ash spill. See Note 5 for additional information.

	Year Ended December 31, 2013
									Total
	Regulated			International		Commercial			Reportable
(in millions)	Utilities			Energy		Portfolio			Segments		Other			Eliminations			Total
Unaffiliated Revenues(a)(b)(c)	$	20,871		$	1,546	$	254		$	22,671	$	85		$	—		$	22,756
Intersegment Revenues	39			—		6			45		90			(135		)	—
Total Revenues	$	20,910		$	1,546	$	260		$	22,716	$	175		$	(135	)	$	22,756
Interest Expense	$	986		$	86	$	61		$	1,133	$	416		$	(6	)	$	1,543
Depreciation and amortization	2,323			100		110			2,533		135			—			2,668
Equity in earnings of unconsolidated affiliates	(1		)	110		7			116		6			—			122
Income tax expense (benefit)	1,522			166		(148		)	1,540		(335		)	—			1,205
Segment income (loss) (a)(b)(c)(d)(e)(f)(g)	2,504			408		(88		)	2,824		(238		)	(12		)	2,574
Add back noncontrolling interest component																	16
Income from discontinued operations, net of tax																	86
Net income																	$	2,676
Capital investments expenditures and acquisitions	$	5,049		$	67	$	268		$	5,384	$	223		$	—		$	5,607
Segment Assets	99,884			4,998		6,955			111,837		2,754			188			114,779

(a) In May 2013, the PUCO approved a Duke Energy Ohio settlement agreement that provides for a net annual increase in electric distribution revenues beginning in May 2013. This rate increase impacts Regulated Utilities.

(b) In June 2013, NCUC approved a Duke Energy Progress settlement agreement that included an increase in rates in the first year beginning in June 2013. This rate increase impacts Regulated Utilities.

(c) In September 2013, Duke Energy Carolinas implemented revised customer rates approved by the NCUC and the PSCSC. These rate increases impact Regulated Utilities.

(d) Regulated Utilities recorded an impairment charge related to Duke Energy Florida's Crystal River Unit 3. See Note 4 for additional information.

(e) Regulated Utilities recorded an impairment charge related to the letter Duke Energy Progress filed with the NRC requesting the NRC to suspend its review activities associated with the combined construction and operating license (COL) at the Harris site. Regulated Utilities also recorded an impairment charge related to the write-off of the wholesale portion of the Levy investments at Duke Energy Florida in accordance with the 2013 Settlement. See Note 4 for additional information.

(f) Other includes costs to achieve mergers.

(g) Other includes gain from the sale of Duke Energy's ownership interest in DukeNet. See Note 12 for additional information on the sale of DukeNet.

Schedule Of Revenue And Long-Lived Assets, By Geographical Area

Geographical Information

(in millions)	U.S.		Latin America(a)		Consolidated
2015
Consolidated revenues	$	22,371	$	1,088	$	23,459
Consolidated long-lived assets	87,552		2,012		89,564
2014
Consolidated revenues	$	22,508	$	1,417	$	23,925
Consolidated long-lived assets	80,709		2,458		83,167
2013
Consolidated revenues	$	21,211	$	1,545	$	22,756
Consolidated long-lived assets	78,581		2,781		81,362

(a) Change in amounts of long-lived assets in Latin America includes foreign currency translation adjustments on property, plant and equipment and other long-lived asset balances.

Schedule of Revenue, By Products and Services

Products and Services

The following table summarizes revenues of the reportable segments by type.

	Retail		Wholesale		Retail		Wholesale				Total
(in millions)	Electric		Electric		Natural Gas		Natural Gas		Other		Revenues
2015
Regulated Utilities	$	18,695	$	2,014	$	546	$	—	$	807	$	22,062
International Energy	—		1,025		—		63		—		1,088
Commercial Portfolio	—		260		—		—		41		301
Total Reportable Segments	$	18,695	$	3,299	$	546	$	63	$	848	$	23,451
2014
Regulated Utilities	$	19,007	$	1,879	$	571	$	—	$	814	$	22,271
International Energy	—		1,326		—		91		—		1,417
Commercial Portfolio	—		255		—		—		—		255
Total Reportable Segments	$	19,007	$	3,460	$	571	$	91	$	814	$	23,943
2013
Regulated Utilities	$	17,837	$	1,720	$	506	$	—	$	847	$	20,910
International Energy	—		1,447		—		99		—		1,546
Commercial Portfolio	—		260		—		—		—		260
Total Reportable Segments	$	17,837	$	3,427	$	506	$	99	$	847	$	22,716

Duke Energy Ohio [Member]

Segment Reporting Information [Line Items]

Business Segment Data

	Year Ended December 31, 2015
						Total
	Regulated		Commercial			Reportable
(in millions)	Utilities		Portfolio			Segments		Other			Eliminations			Total
Unaffiliated revenues	$	1,872	$	14		$	1,886	$	19		$	—		$	1,905
Intersegment revenues	1		—			1		—			(1		)	—
Total revenues	$	1,873	$	14		$	1,887	$	19		$	(1	)	$	1,905
Interest expense	$	78	$	—		$	78	$	1		$	—		$	79
Depreciation and amortization	226		—			226		1			—			227
Income tax expense (benefit)	105		(5		)	100		(19		)	—			81
Segment income (loss)	191		(8		)	183		(33		)	(1		)	149
Income from discontinued operations, net of tax														23
Net income														$	172
Capital expenditures	$	399	$	—		$	399	$	—		$	—		$	399
Segment assets	7,050		—			7,050		55			(8		)	7,097

	Year Ended December 31, 2014
						Total
	Regulated		Commercial			Reportable
(in millions)	Utilities		Portfolio			Segments		Other			Eliminations			Total
Unaffiliated revenues	$	1,894	$	19		$	1,913	$	—		$	—		$	1,913
Intersegment revenues	1		—			1		—			(1		)	—
Total revenues	$	1,895	$	19		$	1,914	$	—		$	(1	)	$	1,913
Interest expense	$	81	$	5		$	86	$	—		$	—		$	86
Depreciation and amortization	211		2			213		1			—			214
Income tax expense (benefit)	117		(67		)	50		(7		)	—			43
Segment income (loss)(a)	202		(121		)	81		(13		)	—			68
Income from discontinued operations, net of tax														(563		)
Net loss														$	(495	)
Capital expenditures	$	300	$	22		$	322	$	—		$	—		$	322
Segment assets	6,902		3,187			10,089		134			(230		)	9,993

(a) Commercial Portfolio recorded a $94 million pretax impairment charge related to OVEC.

	Year Ended December 31, 2013
						Total
	Regulated		Commercial			Reportable
(in millions)	Utilities		Portfolio			Segments		Other			Eliminations			Total
Total revenues	$	1,765	$	40		$	1,805	$	—		$	—		$	1,805
Interest expense	$	74	$	—		$	74	$	—		$	—		$	74
Depreciation and amortization	200		13			213		—			—			213
Income tax expense (benefit)	91		(36		)	55		(12		)	—			43
Segment income (loss)	151		(65		)	86		(19		)	—			67
Income from discontinued operations, net of tax														35
Net income														$	102
Capital expenditures	$	375	$	58		$	433	$	—		$	—		$	433
Segment assets	6,649		4,170			10,819		99			(155		)	10,763