Commitments and Contingencies (Table)

12 Months Ended

Dec. 31, 2018

SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]

Schedule of Legal Reserves

The table below presents recorded reserves based on management’s best estimate of probable loss for legal matters, excluding asbestos-related reserves, the CertainTeed liquidated damages obligation and the exit obligation in 2017 related to the termination of an EPC contract. Reserves are classified on the Consolidated Balance Sheets in Other within Other Noncurrent Liabilities and Other within Current Liabilities. The reasonably possible range of loss in excess of recorded reserves is not material, other than as described above.

	December 31,
(in millions)	2018		2017
Reserves for Legal Matters
Duke Energy	$	65	$	88
Duke Energy Carolinas	9		30
Progress Energy	54		55
Duke Energy Progress	12		13
Duke Energy Florida	24		24
Piedmont	1		2

Schedule of Additional Possible Losses in Excess of Recorded Environmental Reserves

Additional losses in excess of recorded reserves that could be incurred for the stages of investigation, remediation and monitoring for environmental sites that have been evaluated at this time are not material except as presented in the table below.

(in millions)
Duke Energy	$	46
Duke Energy Carolinas	17
Duke Energy Ohio	19
Piedmont	2

Schedule of Purchase Power Obligations

The following table presents executory purchased power contracts with terms exceeding one year, excluding contracts classified as leases.

		Minimum Purchase Amount at December 31, 2018
	Contract
(in millions)	Expiration	2019		2020		2021		2022		2023		Thereafter		Total
Duke Energy Progress(a)	2022-2031	$	51	$	52	$	53	$	30	$	25	$	215	$	426
Duke Energy Florida(b)	2021-2025	363		380		365		363		382		361		2,214
Duke Energy Ohio(c)(d)	2020-2022	146		117		53		11		—		—		327

(a) Contracts represent 100 percent of net plant output.

(b) Contracts represent between 81 percent and 100 percent of net plant output.

(c) Contracts represent between 1 percent and 8 percent of net plant output.

(d) Excludes PPA with OVEC. See Note 17 for additional information.

Schedule of Natural Gas Supply Contract Commitments

The following table presents future unconditional purchase obligations under natural gas supply and capacity contracts as of December 31, 2018.

(in millions)	Duke Energy		Duke Energy Ohio		Piedmont
2019	$	314	$	38	$	276
2020	287		30		257
2021	255		29		226
2022	225		11		214
2023	148		4		144
Thereafter	1,067		—		1,067
Total	$	2,296	$	112	$	2,184

Schedule of Rent Expense

The following tables present rental expense for operating leases. These amounts are included in Operation, maintenance and other and Fuel used in electric generation and purchased power on the Consolidated Statements of Operations.

	Years Ended December 31,
(in millions)	2018		2017		2016
Duke Energy	$	268	$	241	$	242
Duke Energy Carolinas	49		44		45
Progress Energy	143		130		140
Duke Energy Progress	75		75		68
Duke Energy Florida	68		55		72
Duke Energy Ohio	13		15		16
Duke Energy Indiana	21		23		23

	Years Ended December 31,				Two Months Ended December 31,		Year Ended October 31,
(in millions)	2018		2017		2016		2016
Piedmont	$	11	$	7	$	1	$	5

Schedule of Future Minimum Rental Payments for Operating Leases

The following table presents future minimum lease payments under operating leases, which at inception had a non-cancelable term of more than one year.

	December 31, 2018
			Duke				Duke		Duke		Duke		Duke
	Duke		Energy		Progress		Energy		Energy		Energy		Energy
(in millions)	Energy		Carolinas		Energy		Progress		Florida		Ohio		Indiana		Piedmont
2019	$	239	$	33	$	97	$	49	$	48	$	2	$	6	$	5
2020	219		29		90		46		44		2		5		5
2021	186		19		79		37		42		2		4		5
2022	170		19		76		34		42		2		4		5
2023	160		17		77		35		42		2		5		6
Thereafter	1,017		68		455		314		141		23		66		11
Total	$	1,991	$	185	$	874	$	515	$	359	$	33	$	90	$	37

Schedule of Future Minimum Lease Payments for Capital Leases

The following table presents future minimum lease payments under capital leases.

	December 31, 2018
				Duke						Duke			Duke			Duke		Duke
	Duke			Energy			Progress			Energy			Energy			Energy		Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida			Ohio		Indiana
2019	$	170		$	20		$	45		$	20		$	25		$	2	$	1
2020	174			20			46			21			25			—		1
2021	177			15			45			20			25			—		1
2022	165			15			45			21			24			—		1
2023	165			15			45			21			24			—		1
Thereafter	577			204			230			209			21			—		27
Minimum annual payments	1,428			289			456			312			144			2		32
Less: amount representing interest	(487		)	(180		)	(205		)	(175		)	(30		)	—		(22		)
Total	$	941		$	109		$	251		$	137		$	114		$	2	$	10

SEC Schedule, 12-09, Reserve, Environmental Cost [Member]

SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]

Schedule of Legal Reserves

The following tables contain information regarding reserves for probable and estimable costs related to the various environmental sites. These reserves are recorded in Accounts payable within Current Liabilities and Other within Other Noncurrent Liabilities on the Consolidated Balance Sheets.

				Duke						Duke			Duke			Duke			Duke
	Duke			Energy			Progress			Energy			Energy			Energy			Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida			Ohio			Indiana
Balance at December 31, 2015	$	94		$	10		$	17		$	3		$	14		$	54		$	12
Provisions/adjustments	19			4			7			2			4			7			1
Cash reductions	(15		)	(4		)	(6		)	(2		)	(4		)	(2		)	(3		)
Balance at December 31, 2016	98			10			18			3			14			59			10
Provisions/adjustments	8			3			3			2			2			3			(4		)
Cash reductions	(25		)	(3		)	(6		)	(2		)	(4		)	(15		)	(1		)
Balance at December 31, 2017	81			10			15			3			12			47			5
Provisions/adjustments	26			3			2			3			(2		)	21			1
Cash reductions	(30		)	(2		)	(6		)	(2		)	(4		)	(20		)	(1		)
Balance at December 31, 2018	$	77		$	11		$	11		$	4		$	6		$	48		$	5

As of December 31, 2016, and October 31, 2016 and 2015, Piedmont's environmental reserve was $1 million. As of December 31, 2018, and 2017, the reserve was $2 million.