Fair Value Measurements

12 Months Ended

Dec. 31, 2018

Fair Value Disclosures [Abstract]

Fair Value Measurements

FAIR VALUE MEASUREMENTS

Fair value is the exchange price to sell an asset or transfer a liability in an orderly transaction between market participants at the measurement date. The fair value definition focuses on an exit price versus the acquisition cost. Fair value measurements use market data or assumptions market participants would use in pricing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs may be readily observable, corroborated by market data, or generally unobservable. Valuation techniques maximize the use of observable inputs and minimize use of unobservable inputs. A midmarket pricing convention (the midpoint price between bid and ask prices) is permitted for use as a practical expedient.

Fair value measurements are classified in three levels based on the fair value hierarchy as defined by GAAP. Certain investments are not categorized within the fair value hierarchy. These investments are measured at fair value using the NAV per share practical expedient. The NAV is derived based on the investment cost, less any impairment, plus or minus changes resulting from observable price changes for an identical or similar investment of the same issuer.

Fair value accounting guidance permits entities to elect to measure certain financial instruments that are not required to be accounted for at fair value, such as equity method investments or the company’s own debt, at fair value. The Duke Energy Registrants have not elected to record any of these items at fair value.

Transfers between levels represent assets or liabilities that were previously (i) categorized at a higher level for which the inputs to the estimate became less observable or (ii) classified at a lower level for which the inputs became more observable during the period. The Duke Energy Registrant’s policy is to recognize transfers between levels of the fair value hierarchy at the end of the period. There were no transfers between levels during the years ended December 31, 2018, 2017 and 2016. In addition, for Piedmont, there were no transfers between levels during the two months ended December 31, 2016, and the year ended October 31, 2016.

Valuation methods of the primary fair value measurements disclosed below are as follows.

Investments in equity securities

The majority of investments in equity securities are valued using Level 1 measurements. Investments in equity securities are typically valued at the closing price in the principal active market as of the last business day of the quarter. Principal active markets for equity prices include published exchanges such as the NYSE and the Nasdaq Stock Market. Foreign equity prices are translated from their trading currency using the currency exchange rate in effect at the close of the principal active market. There was no after-hours market activity that was required to be reflected in the reported fair value measurements.

Investments in debt securities

Most investments in debt securities are valued using Level 2 measurements because the valuations use interest rate curves and credit spreads applied to the terms of the debt instrument (maturity and coupon interest rate) and consider the counterparty credit rating. If the market for a particular fixed-income security is relatively inactive or illiquid, the measurement is Level 3.

Commodity derivatives

Commodity derivatives with clearinghouses are classified as Level 1. Other commodity derivatives, including Piedmont's natural gas supply contracts, are primarily valued using internally developed discounted cash flow models that incorporate forward price, adjustments for liquidity (bid-ask spread) and credit or non-performance risk (after reflecting credit enhancements such as collateral), and are discounted to present value. Pricing inputs are derived from published exchange transaction prices and other observable data sources. In the absence of an active market, the last available price may be used. If forward price curves are not observable for the full term of the contract and the unobservable period had more than an insignificant impact on the valuation, the commodity derivative is classified as Level 3. In isolation, increases (decreases) in natural gas forward prices result in favorable (unfavorable) fair value adjustments for natural gas purchase contracts; and increases (decreases) in electricity forward prices result in unfavorable (favorable) fair value adjustments for electricity sales contracts. Duke Energy regularly evaluates and validates pricing inputs used to estimate the fair value of natural gas commodity contracts by a market participant price verification procedure. This procedure provides a comparison of internal forward commodity curves to market participant generated curves.

Interest rate derivatives

Most over-the-counter interest rate contract derivatives are valued using financial models that utilize observable inputs for similar instruments and are classified as Level 2. Inputs include forward interest rate curves, notional amounts, interest rates and credit quality of the counterparties.

Other fair value considerations

See Note 11 for a discussion of the valuation of goodwill and intangible assets.

DUKE ENERGY

The following tables provide recorded balances for assets and liabilities measured at fair value on a recurring basis on the Consolidated Balance Sheets. Derivative amounts in the tables below for all Duke Energy Registrants exclude cash collateral, which is disclosed in Note 14. See Note 15 for additional information related to investments by major security type for the Duke Energy Registrants.

	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

	December 31, 2017
(in millions)	Total Fair Value			Level 1			Level 2			Level 3			Not Categorized
NDTF equity securities	$	4,914		$	4,840		$	—		$	—		$	74
NDTF debt securities	2,174			635			1,539			—			—
Other equity securities	123			123			—			—			—
Other debt securities	241			57			184			—			—
Derivative assets	51			3			20			28			—
Total assets	7,503			5,658			1,743			28			74
Derivative liabilities	(230		)	(2		)	(86		)	(142		)	—
Net assets (liabilities)	$	7,273		$	5,656		$	1,657		$	(114	)	$	74

The following tables provide reconciliations of beginning and ending balances of assets and liabilities measured at fair value using Level 3 measurements. Amounts included in earnings for derivatives are primarily included in Cost of natural gas on the Duke Energy Registrants' Consolidated Statements of Operations and Comprehensive Income. Amounts included in changes of net assets on the Duke Energy Registrants' Consolidated Balance Sheets are included in regulatory assets or liabilities. All derivative assets and liabilities are presented on a net basis.

	December 31, 2018			December 31, 2017
(in millions)	Derivatives (net)			Investments			Derivatives (net)			Total
Balance at beginning of period	$	(114	)	$	5		$	(166	)	$	(161	)
Total pretax realized or unrealized gains included in comprehensive income	—			1			—			1
Purchases, sales, issuances and settlements:
Purchases	57			—			55			55
Sales	—			(6		)	—			(6		)
Settlements	(57		)	—			(47		)	(47		)
Total gains included on the Consolidated Balance Sheet	1			—			44			44
Balance at end of period	$	(113	)	$	—		$	(114	)	$	(114	)

DUKE ENERGY CAROLINAS

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

	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

	December 31, 2017
(in millions)	Total Fair Value			Level 1			Level 2			Not Categorized
NDTF equity securities	$	2,692		$	2,618		$	—		$	74
NDTF debt securities	1,066			204			862			—
Derivative assets	2			—			2			—
Total assets	3,760			2,822			864			74
Derivative liabilities	(35		)	(1		)	(34		)	—
Net assets	$	3,725		$	2,821		$	830		$	74

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

	Investments
	Year Ended December 31,
(in millions)	2017
Balance at beginning of period	$	3
Total pretax realized or unrealized gains included in comprehensive income	1
Purchases, sales, issuances and settlements:
Sales	(4		)
Balance at end of period	$	—

PROGRESS ENERGY

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

	December 31, 2018								December 31, 2017
(in millions)	Total Fair Value			Level 1		Level 2			Total Fair Value			Level 1			Level 2
NDTF equity securities	$	1,991		$	1,991	$	—		$	2,222		$	2,222		$	—
NDTF debt securities	1,162			427		735			1,108			431			677
Other debt securities	64			17		47			59			12			47
Derivative assets	4			—		4			3			1			2
Total assets	3,221			2,435		786			3,392			2,666			726
Derivative liabilities	(44		)	—		(44		)	(36		)	(1		)	(35		)
Net assets	$	3,177		$	2,435	$	742		$	3,356		$	2,665		$	691

DUKE ENERGY PROGRESS

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

	December 31, 2018								December 31, 2017
(in millions)	Total Fair Value			Level 1		Level 2			Total Fair Value			Level 1			Level 2
NDTF equity securities	$	1,588		$	1,588	$	—		$	1,795		$	1,795		$	—
NDTF debt securities	906			294		612			796			243			553
Other debt securities	6			6		—			1			1			—
Derivative assets	4			—		4			2			1			1
Total assets	2,504			1,888		616			2,594			2,040			554
Derivative liabilities	(27		)	—		(27		)	(18		)	(1		)	(17		)
Net assets	$	2,477		$	1,888	$	589		$	2,576		$	2,039		$	537

DUKE ENERGY FLORIDA

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

	December 31, 2018								December 31, 2017
(in millions)	Total Fair Value			Level 1		Level 2			Total Fair Value			Level 1		Level 2
NDTF equity securities	$	403		$	403	$	—		$	427		$	427	$	—
NDTF debt securities	256			133		123			312			188		124
Other debt securities	48			1		47			48			1		47
Derivative assets	—			—		—			1			—		1
Total assets	707			537		170			788			616		172
Derivative liabilities	(9		)	—		(9		)	(12		)	—		(12		)
Net assets	$	698		$	537	$	161		$	776		$	616	$	160

DUKE ENERGY OHIO

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

	December 31, 2018								December 31, 2017
(in millions)	Total Fair Value			Level 2			Level 3		Total Fair Value			Level 2			Level 3
Derivative assets	$	6		$	—		$	6	$	1		$	—		$	1
Derivative liabilities	(5		)	(5		)	—		(5		)	(5		)	—
Net assets (liabilities)	$	1		$	(5	)	$	6	$	(4	)	$	(5	)	$	1

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)
	Years Ended December 31,
(in millions)	2018			2017
Balance at beginning of period	$	1		$	5
Purchases, sales, issuances and settlements:
Purchases	7			3
Settlements	(4		)	(4		)
Total gains included on the Consolidated Balance Sheet	2			(3		)
Balance at end of period	$	6		$	1

DUKE ENERGY INDIANA

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

	December 31, 2018								December 31, 2017
(in millions)	Total Fair Value		Level 1		Level 2		Level 3		Total Fair Value		Level 1		Level 2		Level 3
Other equity securities	$	67	$	67	$	—	$	—	$	97	$	97	$	—	$	—
Other debt securities	41		—		41		—		31		—		31		—
Derivative assets	23		1		—		22		27		—		—		27
Total assets	$	131	$	68	$	41	$	22	$	155	$	97	$	31	$	27

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)
	Years Ended December 31,
(in millions)	2018			2017
Balance at beginning of period	$	27		$	16
Purchases, sales, issuances and settlements:
Purchases	50			52
Settlements	(53		)	(43		)
Total (losses) gains included on the Consolidated Balance Sheet	(2		)	2
Balance at end of period	$	22		$	27

PIEDMONT

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

	December 31, 2018								December 31, 2017
(in millions)	Total Fair Value			Level 1		Level 3			Total Fair Value			Level 1		Level 3
Other debt securities	$	—		$	—	$	—		$	1		$	1	$	—
Derivative assets	3			3		—			2			2		—
Total assets	3			3		—			3			3		—
Derivative liabilities	(141		)	—		(141		)	(142		)	—		(142		)
Net (liabilities) assets	$	(138	)	$	3	$	(141	)	$	(139	)	$	3	$	(142	)

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)
	Years Ended December 31,
(in millions)	2018			2017
Balance at beginning of period	$	(142	)	$	(187	)
Total gains and settlements	1			45
Balance at end of period	$	(141	)	$	(142	)

QUANTITATIVE INFORMATION ABOUT UNOBSERVABLE INPUTS

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

	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	)

	December 31, 2017
	Fair Value
Investment Type	(in millions)			Valuation Technique	Unobservable Input	Range
Duke Energy Ohio
FTRs	$	1		RTO auction pricing	FTR price – per MWh	$	0.07		–	$	1.41
Duke Energy Indiana
FTRs	27			RTO auction pricing	FTR price – per MWh	(0.77		)	–	7.44
Piedmont
Natural gas contracts	(142		)	Discounted cash flow	Forward natural gas curves — price per MMBtu	2.10			–	2.88
Duke Energy
Total Level 3 derivatives	$	(114	)

OTHER FAIR VALUE DISCLOSURES

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.

	December 31, 2018				December 31, 2017
(in millions)	Book Value		Fair Value		Book Value		Fair Value
Duke Energy(a)	$	54,529	$	54,534	$	52,279	$	55,331
Duke Energy Carolinas	10,939		11,471		10,103		11,372
Progress Energy	18,911		19,885		17,837		20,000
Duke Energy Progress	8,204		8,300		7,357		7,992
Duke Energy Florida	7,321		7,742		7,095		7,953
Duke Energy Ohio	2,165		2,239		2,067		2,249
Duke Energy Indiana	3,782		4,158		3,783		4,464
Piedmont	2,138		2,180		2,037		2,209

(a) Book value of long-term debt includes $1.6 billion as of December 31, 2018, and $1.7 billion as of December 31, 2017, 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.

At both December 31, 2018, and December 31, 2017, fair value of cash and cash equivalents, accounts and notes receivable, accounts payable, notes payable and commercial paper, and nonrecourse notes payable of VIEs are not materially different from their carrying amounts because of the short-term nature of these instruments and/or because the stated rates approximate market rates.