Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2019

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets. Derivative amounts in the tables below for all Duke Energy Registrants exclude cash collateral, which is disclosed in Note 10. See Note 11 for additional information related to investments by major security type for the Duke Energy Registrants.

	March 31, 2019
(in millions)	Total Fair Value			Level 1			Level 2			Level 3			Not Categorized
NDTF equity securities	$	5,061		$	4,998		$	—		$	—		$	63
NDTF debt securities	2,302			630			1,672			—			—
Other equity securities	112			112			—			—			—
Other debt securities	310			103			207			—			—
Derivative assets	35			2			27			6			—
Total assets	7,820			5,845			1,906			6			63
Derivative liabilities	(244		)	(23		)	(100		)	(121		)	—
Net assets (liabilities)	$	7,576		$	5,822		$	1,806		$	(115	)	$	63

	December 31, 2018
(in millions)	Total Fair Value			Level 1			Level 2			Level 3			Not Categorized
NDTF equity securities	$	4,475		$	4,410		$	—		$	—		$	65
NDTF debt securities	2,231			576			1,655			—			—
Other equity securities	99			99			—			—			—
Other debt securities	270			67			203			—			—
Derivative assets	57			4			25			28			—
Total assets	7,132			5,156			1,883			28			65
Derivative liabilities	(242		)	(11		)	(90		)	(141		)	—
Net assets (liabilities)	$	6,890		$	5,145		$	1,793		$	(113	)	$	65

Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs

The following tables provide reconciliations of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements.

	Derivatives (net)
	Three Months Ended March 31,
(in millions)	2019			2018
Balance at beginning of period	$	(113	)	$	(114	)
Purchases, sales, issuances and settlements:
Settlements	(12		)	(14		)
Total gains included on the Condensed Consolidated Balance Sheet	10			4
Balance at end of period	$	(115	)	$	(124	)

Quantitative Information Table - Level 3

The following tables include quantitative information about the Duke Energy Registrants' derivatives classified as Level 3.

	March 31, 2019
	Fair Value
Investment Type	(in millions)			Valuation Technique	Unobservable Input	Range
Duke Energy Ohio
FTRs	$	1		RTO auction pricing	FTR price – per MWh	$	0.17		-	$	2.40
Duke Energy Indiana
FTRs	5			RTO auction pricing	FTR price – per MWh	(0.42		)	-	7.85
Piedmont
Natural gas contracts	(121		)	Discounted cash flow	Forward natural gas curves – price per MMBtu	2.03			-	3.15
Duke Energy
Total Level 3 derivatives	$	(115	)

	December 31, 2018
	Fair Value
Investment Type	(in millions)			Valuation Technique	Unobservable Input	Range
Duke Energy Ohio
FTRs	$	6		RTO auction pricing	FTR price – per MWh	$	1.19		-	$	4.59
Duke Energy Indiana
FTRs	22			RTO auction pricing	FTR price – per MWh	(2.07		)	-	8.27
Piedmont
Natural gas contracts	(141		)	Discounted cash flow	Forward natural gas curves – price per MMBtu	1.87			-	2.95
Duke Energy
Total Level 3 derivatives	$	(113	)

Schedule Of Long Term Debt Fair Value

The fair value and book value of long-term debt, including current maturities, is summarized in the following table. Estimates determined are not necessarily indicative of amounts that could have been settled in current markets. Fair value of long-term debt uses Level 2 measurements.

	March 31, 2019				December 31, 2018
(in millions)	Book Value		Fair Value		Book Value		Fair Value
Duke Energy(a)	$	56,182	$	58,242	$	54,529	$	54,534
Duke Energy Carolinas	10,965		11,951		10,939		11,471
Progress Energy	19,251		20,942		18,911		19,885
Duke Energy Progress	9,048		9,469		8,204		8,300
Duke Energy Florida	7,265		8,000		7,321		7,742
Duke Energy Ohio	2,960		3,149		2,165		2,239
Duke Energy Indiana	3,722		4,242		3,782		4,158
Piedmont	2,138		2,243		2,138		2,180

(a) Book value of long-term debt includes $1.5 billion as of March 31, 2019, and $1.6 billion as of December 31, 2018, of unamortized debt discount and premium, net in purchase accounting adjustments related to the mergers with Progress Energy and Piedmont that are excluded from fair value of long-term debt.

Duke Energy Carolinas [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets.

	March 31, 2019
(in millions)	Total Fair Value			Level 1		Level 2			Not Categorized
NDTF equity securities	$	2,791		$	2,728	$	—		$	63
NDTF debt securities	1,122			212		910			—
Derivative assets	5			—		5			—
Total assets	3,918			2,940		915			63
Derivative liabilities	(39		)	—		(39		)	—
Net assets	$	3,879		$	2,940	$	876		$	63

	December 31, 2018
(in millions)	Total Fair Value			Level 1		Level 2			Not Categorized
NDTF equity securities	$	2,484		$	2,419	$	—		$	65
NDTF debt securities	1,069			149		920			—
Derivative assets	3			—		3			—
Total assets	3,556			2,568		923			65
Derivative liabilities	(33		)	—		(33		)	—
Net assets	$	3,523		$	2,568	$	890		$	65

Progress Energy [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets.

	March 31, 2019								December 31, 2018
(in millions)	Total Fair Value			Level 1		Level 2			Total Fair Value			Level 1		Level 2
NDTF equity securities	$	2,270		$	2,270	$	—		$	1,991		$	1,991	$	—
NDTF debt securities	1,180			418		762			1,162			427		735
Other debt securities	96			47		49			64			17		47
Derivative assets	8			—		8			4			—		4
Total assets	3,554			2,735		819			3,221			2,435		786
Derivative liabilities	(44		)	—		(44		)	(44		)	—		(44		)
Net assets	$	3,510		$	2,735	$	775		$	3,177		$	2,435	$	742

Duke Energy Progress [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets.

	March 31, 2019								December 31, 2018
(in millions)	Total Fair Value			Level 1		Level 2			Total Fair Value			Level 1		Level 2
NDTF equity securities	$	1,812		$	1,812	$	—		$	1,588		$	1,588	$	—
NDTF debt securities	926			298		628			906			294		612
Other debt securities	3			3		—			6			6		—
Derivative assets	8			—		8			4			—		4
Total assets	2,749			2,113		636			2,504			1,888		616
Derivative liabilities	(12		)	—		(12		)	(27		)	—		(27		)
Net assets	$	2,737		$	2,113	$	624		$	2,477		$	1,888	$	589

Duke Energy Florida [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets.

	March 31, 2019								December 31, 2018
(in millions)	Total Fair Value			Level 1		Level 2			Total Fair Value			Level 1		Level 2
NDTF equity securities	$	458		$	458	$	—		$	403		$	403	$	—
NDTF debt securities	254			120		134			256			133		123
Other debt securities	50			1		49			48			1		47
Total assets	762			579		183			707			537		170
Derivative liabilities	(18		)	—		(18		)	(9		)	—		(9		)
Net assets	$	744		$	579	$	165		$	698		$	537	$	161

Duke Energy Ohio [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

The recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets were not material for the three months ended March 31, 2019, and 2018.

Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs

Duke Energy Indiana [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets.

	March 31, 2019								December 31, 2018
(in millions)	Total Fair Value		Level 1		Level 2		Level 3		Total Fair Value		Level 1		Level 2		Level 3
Other equity securities	$	76	$	76	$	—	$	—	$	67	$	67	$	—	$	—
Other debt securities	42		—		42		—		41		—		41		—
Derivative assets	5		—		—		5		23		1		—		22
Total assets	$	123	$	76	$	42	$	5	$	131	$	68	$	41	$	22

Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs

The following table provides a reconciliation of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements.

	Derivatives (net)
	Three Months Ended March 31,
(in millions)	2019			2018
Balance at beginning of period	$	22		$	27
Purchases, sales, issuances and settlements:
Settlements	(10		)	(14		)
Total losses included on the Condensed Consolidated Balance Sheet	(7		)	(6		)
Balance at end of period	$	5		$	7

Piedmont Natural Gas [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets.

	March 31, 2019								December 31, 2018
(in millions)	Total Fair Value			Level 1		Level 3			Total Fair Value			Level 1		Level 3
Derivative assets	$	2		$	2	$	—		$	3		3		—
Derivative liabilities	(121		)	—		(121		)	(141		)	—		(141		)
Net (liabilities) assets	$	(119	)	$	2	$	(121	)	$	(138	)	$	3	$	(141	)

Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs

The following table provides a reconciliation of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements.

	Derivatives (net)
	Three Months Ended March 31,
(in millions)	2019			2018
Balance at beginning of period	$	(141	)	$	(142	)
Total gains and settlements	20			10
Balance at end of period	$	(121	)	$	(132	)