Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Line Items]

Schedule of Components of Income Tax Expense (Benefit)

Components of Income Tax Expense

	Year Ended December 31, 2016
				Duke						Duke			Duke		Duke			Duke
	Duke			Energy			Progress			Energy			Energy		Energy			Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida		Ohio			Indiana
Current income taxes
Federal	$	—		$	139		$	15		$	(59	)	$	76	$	(7	)	$	7
State	(15		)	25			(19		)	(25		)	22		(13		)	6
Foreign	2			—			—			—			—		—			—
Total current income taxes	(13		)	164			(4		)	(84		)	98		(20		)	13
Deferred income taxes
Federal	1,064			430			486			350			199		88			202
State	117			45			50			40			25		11			11
Total deferred income taxes(a)	1,181			475			536			390			224		99			213
Investment tax credit amortization	(12		)	(5		)	(5		)	(5		)	—		(1		)	(1		)
Income tax expense from continuing operations	1,156			634			527			301			322		78			225
Tax (benefit) expense from discontinued operations	(30		)	—			1			—			—		(36		)	—
Total income tax expense included in Consolidated Statements of Operations	$	1,126		$	634		$	528		$	301		$	322	$	42		$	225

(a) Includes benefits of net operating loss (NOL) carryforwards and tax credit carryforwards of $648 million at Duke Energy, $4 million at Duke Energy Carolinas, $190 million at Progress Energy, $60 million at Duke Energy Progress, $49 million at Duke Energy Florida, $26 million at Duke Energy Ohio and $58 million at Duke Energy Indiana.

	Year Ended December 31, 2015
				Duke						Duke			Duke			Duke			Duke
	Duke			Energy			Progress			Energy			Energy			Energy			Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida			Ohio			Indiana
Current income taxes
Federal	$	—		$	216		$	(193	)	$	(56	)	$	1		$	(18	)	$	(86	)
State	(12		)	14			1			(4		)	(7		)	(1		)	(12		)
Foreign	4			—			—			—			—			—			—
Total current income taxes	(8		)	230			(192		)	(60		)	(6		)	(19		)	(98		)
Deferred income taxes
Federal	1,097			345			694			334			290			96			245
State	181			57			27			27			58			5			17
Total deferred income taxes(a)	1,278			402			721			361			348			101			262
Investment tax credit amortization	(14		)	(5		)	(7		)	(7		)	—			(1		)	(1		)
Income tax expense from continuing operations	1,256			627			522			294			342			81			163
Tax expense (benefit) from discontinued operations	89			—			(1		)	—			—			22			—
Total income tax expense included in Consolidated Statements of Operations	$	1,345		$	627		$	521		$	294		$	342		$	103		$	163

(a) Includes benefits of NOL carryforwards and utilization of NOL and tax credit carryforwards of $264 million at Duke Energy, $15 million at Duke Energy Carolinas, $119 million at Progress Energy, $21 million at Duke Energy Progress, $84 million at Duke Energy Florida, $3 million at Duke Energy Ohio and $45 million at Duke Energy Indiana.

	Year Ended December 31, 2014
				Duke						Duke			Duke			Duke			Duke
	Duke			Energy			Progress			Energy			Energy			Energy			Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida			Ohio			Indiana
Current income taxes
Federal	$	—		$	161		$	(466	)	$	(184	)	$	(53	)	$	(73	)	$	(112	)
State	56			51			(8		)	14			1			3			1
Foreign	6			—			—			—			—			—			—
Total current income taxes	62			212			(474		)	(170		)	(52		)	(70		)	(111		)
Deferred income taxes
Federal	1,144			407			938			436			350			113			294
State	35			(25		)	84			25			52			1			15
Total deferred income taxes(a)(b)	1,179			382			1,022			461			402			114			309
Investment tax credit amortization	(16		)	(6		)	(8		)	(6		)	(1		)	(1		)	(1		)
Income tax expense from continuing operations	1,225			588			540			285			349			43			197
Tax expense (benefit) from discontinued operations	149			—			(4		)	—			—			(300		)	—
Total income tax expense (benefit) included in Consolidated Statements of Operations	$	1,374		$	588		$	536		$	285		$	349		$	(257	)	$	197

(a) There were no benefits of NOL carryforwards.

(b) Includes utilization of NOL carryforwards of $1,544 million at Duke Energy, $345 million at Duke Energy Carolinas, $530 million at Progress Energy, $291 million at Duke Energy Progress, $64 million at Duke Energy Florida, $56 million at Duke Energy Ohio and $141 million at Duke Energy Indiana.

Schedule of Income before Income Tax, Domestic and Foreign

Duke Energy Income from Continuing Operations before Income Taxes

	Years Ended December 31,
(in millions)	2016		2015		2014
Domestic	$	3,689	$	3,831	$	3,637
Foreign	45		79		126
Income from continuing operations before income taxes	$	3,734	$	3,910	$	3,763

Summary of Effective Tax Rates

The following tables present a reconciliation of income tax expense at the U.S. federal statutory tax rate to the actual tax expense from continuing operations.

	Year Ended December 31, 2016
				Duke						Duke			Duke			Duke			Duke
	Duke			Energy			Progress			Energy			Energy			Energy			Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida			Ohio			Indiana
Income tax expense, computed at the statutory rate of 35 percent	$	1,307		$	630		$	548		$	315		$	306		$	95		$	212
State income tax, net of federal income tax effect	64			46			20			10			30			(2		)	11
AFUDC equity income	(70		)	(36		)	(26		)	(17		)	(9		)	(2		)	(6		)
Renewable energy production tax credits	(97		)	—			—			—			—			—			—
Audit adjustment	5			3			—			—			—			—			—
Tax true-up	(14		)	(14		)	(11		)	(3		)	(9		)	(16		)	2
Other items, net	(39		)	5			(4		)	(4		)	4			3			6
Income tax expense from continuing operations	$	1,156		$	634		$	527		$	301		$	322		$	78		$	225
Effective tax rate	31.0		%	35.2		%	33.7		%	33.4		%	36.9		%	28.9		%	37.1		%

	Year Ended December 31, 2015
				Duke						Duke			Duke			Duke			Duke
	Duke			Energy			Progress			Energy			Energy			Energy			Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida			Ohio			Indiana
Income tax expense, computed at the statutory rate of 35 percent	$	1,369		$	598		$	555		$	302		$	330		$	81		$	168
State income tax, net of federal income tax effect	109			46			18			15			33			2			2
AFUDC equity income	(58		)	(34		)	(19		)	(17		)	(3		)	(1		)	(4		)
Renewable energy production tax credits	(72		)	—			(1		)	—			—			—			—
Audit adjustment	(22		)	—			(23		)	1			(24		)	—			—
Tax true-up	2			2			(3		)	(4		)	2			(5		)	(9		)
Other items, net	(72		)	15			(5		)	(3		)	4			4			6
Income tax expense from continuing operations	$	1,256		$	627		$	522		$	294		$	342		$	81		$	163
Effective tax rate	32.1		%	36.7		%	32.9		%	34.2		%	36.3		%	35.2		%	34.0		%

	Year Ended December 31, 2014
				Duke						Duke			Duke			Duke			Duke
	Duke			Energy			Progress			Energy			Energy			Energy			Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida			Ohio			Indiana
Income tax expense, computed at the statutory rate of 35 percent	$	1,317		$	581		$	497		$	263		$	314		$	39		$	195
State income tax, net of federal income tax effect	59			17			49			25			34			3			10
AFUDC equity income	(47		)	(32		)	(9		)	(9		)	—			(1		)	(5		)
Renewable energy production tax credits	(67		)	—			—			—			—			—			—
Other items, net	(37		)	22			3			6			1			2			(3		)
Income tax expense from continuing operations	$	1,225		$	588		$	540		$	285		$	349		$	43		$	197
Effective tax rate	32.6		%	35.4		%	38.0		%	37.9		%	38.9		%	38.9		%	35.5		%

Schedule of Deferred Tax Assets and Liabilities

	December 31, 2015
				Duke						Duke			Duke			Duke			Duke
	Duke			Energy			Progress			Energy			Energy			Energy			Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida			Ohio			Indiana
Deferred credits and other liabilities	$	201		$	38		$	115		$	25		$	66		$	29		$	5
Capital lease obligations	63			9			—			—			—			—			2
Pension, post-retirement and other employee benefits	580			46			186			92			82			24			40
Progress Energy merger purchase accounting adjustments(a)	1,009			—			—			—			—			—			—
Tax credits and NOL carryforwards	3,631			170			997			163			177			25			215
Investments and other assets	—			—			—			—			—			3			—
Other	206			20			48			2			46			37			20
Valuation allowance	(93		)	—			(38		)	—			—			—			—
Total deferred income tax assets	5,597			283			1,308			282			371			118			282
Investments and other assets	(1,573		)	(1,057		)	(412		)	(228		)	(201		)	—			(7		)
Accelerated depreciation rates	(12,939		)	(4,429		)	(4,169		)	(2,325		)	(1,868		)	(1,356		)	(1,797		)
Regulatory assets and deferred debits, net	(3,633		)	(943		)	(1,517		)	(756		)	(762		)	(169		)	(135		)
Total deferred income tax liabilities	(18,145		)	(6,429		)	(6,098		)	(3,309		)	(2,831		)	(1,525		)	(1,939		)
Net deferred income tax liabilities	$	(12,548	)	$	(6,146	)	$	(4,790	)	$	(3,027	)	$	(2,460	)	$	(1,407	)	$	(1,657	)

(a) Primarily related to capital lease obligations and debt fair value adjustments.

Net Deferred Income Tax Liability Components

	December 31, 2016
				Duke						Duke			Duke			Duke			Duke
	Duke			Energy			Progress			Energy			Energy			Energy			Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida			Ohio			Indiana
Deferred credits and other liabilities	$	382		$	66		$	126		$	40		$	93		$	21		$	4
Capital lease obligations	60			8			—			—			—			—			1
Pension, post-retirement and other employee benefits	561			16			199			91			96			22			37
Progress Energy merger purchase accounting adjustments(a)	918			—			—			—			—			—			—
Tax credits and NOL carryforwards	4,682			192			1,165			222			232			49			278
Investments and other assets	—			—			—			—			—			3			—
Other	205			16			35			8			—			5			9
Valuation allowance	(96		)	—			(12		)	—			—			—			—
Total deferred income tax assets	6,712			298			1,513			361			421			100			329
Investments and other assets	(1,892		)	(1,149		)	(597		)	(313		)	(297		)	—			(21		)
Accelerated depreciation rates	(14,872		)	(4,664		)	(4,490		)	(2,479		)	(2,038		)	(1,404		)	(1,938		)
Regulatory assets and deferred debits, net	(4,103		)	(1,029		)	(1,672		)	(892		)	(780		)	(139		)	(270		)
Total deferred income tax liabilities	(20,867		)	(6,842		)	(6,759		)	(3,684		)	(3,115		)	(1,543		)	(2,229		)
Net deferred income tax liabilities	$	(14,155	)	$	(6,544	)	$	(5,246	)	$	(3,323	)	$	(2,694	)	$	(1,443	)	$	(1,900	)

(a) Primarily related to capital lease obligations and debt fair value adjustments.

Summary of Tax Credit Carryforwards

The following table presents the expiration of tax credits and NOL carryforwards.

	December 31, 2016
(in millions)	Amount		Expiration Year
Investment tax credits	$	1,143	2027	—	2036
Alternative minimum tax credits	1,151		Indefinite
Federal NOL carryforwards	1,267		2020	—	2036
State NOL carryforwards and credits(a)	248		2017	—	2036
Foreign NOL carryforwards(b)	12		2026	—	2036
Foreign Tax Credits	859		2024	—	2026
Charitable Carryforwards	2		2017	—	2019
Total tax credits and NOL carryforwards	$	4,682

(a) A valuation allowance of $84 million has been recorded on the state NOL carryforwards, as presented in the Net Deferred Income Tax Liability Components table.

(b) A valuation allowance of $12 million has been recorded on the foreign NOL carryforwards, as presented in the Net Deferred Income Tax Liability Components table.

Schedule of Unrecognized Tax Benefits Roll Forward

The following tables present changes to unrecognized tax benefits.

	Year Ended December 31, 2016
				Duke						Duke			Duke		Duke
	Duke			Energy			Progress			Energy			Energy		Energy
(in millions)	Energy			Carolinas			Energy			Progress			Ohio		Indiana
Unrecognized tax benefits – January 1	$	88		$	72		$	1		$	3		$	—	$	1
Unrecognized tax benefits increases (decreases)
Gross increases – tax positions in prior periods	—			—			—			—			4		—
Gross decreases – tax positions in prior periods	(4		)	(4		)	(1		)	(1		)	—		—
Decreases due to settlements	(68		)	(67		)	—			—			—		(1		)
Reduction due to lapse of statute of limitations	1			—			2			—			—		—
Total changes	(71		)	(71		)	1			(1		)	4		(1		)
Unrecognized tax benefits – December 31	$	17		$	1		$	2		$	2		$	4	$	—

	Year Ended December 31, 2015
				Duke						Duke			Duke			Duke
	Duke			Energy			Progress			Energy			Energy			Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida			Indiana
Unrecognized tax benefits – January 1	$	213		$	160		$	32		$	23		$	8		$	1
Unrecognized tax benefits increases (decreases)
Gross increases – tax positions in prior periods	—			—			1			1			—			—
Gross decreases – tax positions in prior periods	(48		)	(45		)	—			—			—			—
Decreases due to settlements	(45		)	(43		)	—			—			—			—
Reduction due to lapse of statute of limitations	(32		)	—			(32		)	(21		)	(8		)	—
Total changes	(125		)	(88		)	(31		)	(20		)	(8		)	—
Unrecognized tax benefits – December 31	$	88		$	72		$	1		$	3		$	—		$	1

	Year Ended December 31, 2014
				Duke						Duke		Duke		Duke
	Duke			Energy			Progress			Energy		Energy		Energy
(in millions)	Energy			Carolinas			Energy			Progress		Florida		Indiana
Unrecognized tax benefits – January 1	$	230		$	171		$	32		$	22	$	8	$	1
Unrecognized tax benefits increases (decreases)
Gross increases — tax positions in prior periods	—			—			1			1		—		—
Gross decreases – tax positions in prior periods	(2		)	—			—			—		—		—
Decreases due to settlements	(15		)	(11		)	(1		)	—		—		—
Total changes	(17		)	(11		)	—			1		—		—
Unrecognized tax benefits – December 31	$	213		$	160		$	32		$	23	$	8	$	1

Schedule of Unrecognized Tax Benefits

The following table includes additional information regarding the Duke Energy Registrants' unrecognized tax benefits. It is reasonably possible that Duke Energy could reflect an approximate $8 million reduction and Duke Energy Carolinas could reflect an approximate $1 million reduction in unrecognized tax benefits within the next 12 months. All other Duke Energy Registrants do not anticipate a material increase or decrease in unrecognized tax benefits within the next 12 months.

	December 31, 2016
			Duke				Duke		Duke		Duke		Duke
	Duke		Energy		Progress		Energy		Energy		Energy		Energy
(in millions)	Energy		Carolinas		Energy		Progress		Florida		Ohio		Indiana
Amount that if recognized, would affect the effective tax rate or regulatory liability(a)	$	8	$	1	$	2	$	2	$	—	$	—	$	—
Amount that if recognized, would be recorded as a component of discontinued operations	5		—		—		—		—		2		—

(a) Duke Energy, Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida and Duke Energy Indiana are unable to estimate the specific amounts that would affect the effective tax rate versus the regulatory liability.

Summary of Income Tax Contingencies

The following tables include interest recognized in the Consolidated Statements of Operations and the Consolidated Balance Sheets.

	Year Ended December 31, 2016
			Duke				Duke		Duke
	Duke		Energy		Progress		Energy		Energy
(in millions)	Energy		Carolinas		Energy		Progress		Florida
Net interest income recognized related to income taxes	$	—	$	—	$	1	$	—	$	2
Net interest expense recognized related to income taxes	—		7		—		—		—
Interest payable related to income taxes	4		23		1		1		—

	Year Ended December 31, 2015
			Duke				Duke		Duke		Duke
	Duke		Energy		Progress		Energy		Energy		Energy
(in millions)	Energy		Carolinas		Energy		Progress		Florida		Indiana
Net interest income recognized related to income taxes	$	12	$	—	$	2	$	2	$	1	$	1
Net interest expense recognized related to income taxes	—		1		—		—		—		—
Interest receivable related to income taxes	3		—		—		—		—		3
Interest payable related to income taxes	—		14		—		1		—		—

	Year Ended December 31, 2014
			Duke				Duke		Duke		Duke		Duke
	Duke		Energy		Progress		Energy		Energy		Energy		Energy
(in millions)	Energy		Carolinas		Energy		Progress		Florida		Ohio		Indiana
Net interest income recognized related to income taxes	$	6	$	—	$	3	$	—	$	1	$	4	$	4
Net interest expense recognized related to income taxes	—		1		—		1		—		—		—
Interest receivable related to income taxes	—		—		—		—		—		—		2
Interest payable related to income taxes	13		13		5		3		5		—		—