Debt and Credit Facilities (Tables)

12 Months Ended

Dec. 31, 2016

Debt Disclosure [Abstract]

Schedule of Debt

The following table shows the significant components of Current maturities of Long-Term Debt on the Consolidated Balance Sheets. The Duke Energy Registrants currently anticipate satisfying these obligations with cash on hand and proceeds from additional borrowings.

(in millions)	Maturity Date	Interest Rate		December 31, 2016
Unsecured Debt
Duke Energy (Parent)	April 2017	1.226	%	$	400
Duke Energy (Parent)	August 2017	1.625	%	700
Piedmont Natural Gas	September 2017	8.510	%	35
First Mortgage Bonds
Duke Energy Progress	March 2017	1.146	%	250
Duke Energy Florida	September 2017	5.800	%	250
Duke Energy Progress	November 2017	1.111	%	200
Secured
Duke Energy	June 2017	2.365	%	45
Duke Energy	June 2017	2.260	%	34
Tax-exempt Bonds
Duke Energy Carolinas	February 2017	3.600	%	77
Duke Energy Carolinas	February 2017	0.810	%	10
Duke Energy Carolinas	February 2017	0.790	%	25
Other(a)				293
Current maturities of long-term debt				$	2,319

(a) Includes capital lease obligations, amortizing debt and small bullet maturities.

The following tables show short-term obligations classified as long-term debt.

	December 31, 2016
			Duke		Duke		Duke		Duke
	Duke		Energy		Energy		Energy		Energy
(in millions)	Energy		Carolinas		Progress		Ohio		Indiana
Tax-exempt bonds	$	347	$	35	$	—	$	27	$	285
Commercial paper(a)	625		300		150		25		150
Total	$	972	$	335	$	150	$	52	$	435

	December 31, 2015
			Duke		Duke		Duke		Duke
	Duke		Energy		Energy		Energy		Energy
(in millions)	Energy		Carolinas		Progress		Ohio		Indiana
Tax-exempt bonds	$	347	$	35	$	—	$	27	$	285
Commercial paper(a)	625		300		150		25		150
Total	$	972	$	335	$	150	$	52	$	435

(a) Progress Energy amounts are equal to Duke Energy Progress amounts.

The following tables summarize outstanding debt.

	December 31, 2016
	Weighted
	Average					Duke						Duke			Duke			Duke			Duke
	Interest		Duke			Energy			Progress			Energy			Energy			Energy			Energy
(in millions)	Rate		Energy			Carolinas			Energy			Progress			Florida			Ohio			Indiana
Unsecured debt, maturing 2017 - 2073	4.30	%	$	17,812		$	1,150		$	3,551		$	—		$	150		$	810		$	415
Secured debt, maturing 2017 - 2037	2.60	%	3,909			425			1,819			300			1,519			—			—
First mortgage bonds, maturing 2017 - 2046(a)	4.61	%	21,879			7,410			10,800			6,425			4,375			1,000			2,669
Capital leases, maturing 2018 - 2051(b)	4.48	%	1,100			22			285			142			143			7			11
Tax-exempt bonds, maturing 2017 - 2041(c)	2.84	%	1,053			355			48			48			—			77			572
Notes payable and commercial paper(d)	1.01	%	3,112			—			—			—			—			—			—
Money pool/intercompany borrowings(e)			—			300			1,902			150			297			41			150
Fair value hedge carrying value adjustment			6			6			—			—			—			—			—
Unamortized debt discount and premium, net(f)			1,753			(20		)	(31		)	(16		)	(10		)	(28		)	(9		)
Unamortized debt issuance costs(g)			(242		)	(45		)	(104		)	(38		)	(52		)	(7		)	(22		)
Total debt	4.07	%	$	50,382		$	9,603		$	18,270		$	7,011		$	6,422		$	1,900		$	3,786
Short-term notes payable and commercial paper			(2,487		)	—			—			—			—			—			—
Short-term money pool/intercompany borrowings			—			—			(729		)	—			(297		)	(16		)	—
Current maturities of long-term debt(h)			(2,319		)	(116		)	(778		)	(452		)	(326		)	(1		)	(3		)
Total long-term debt(h)			$	45,576		$	9,487		$	16,763		$	6,559		$	5,799		$	1,883		$	3,783

(a) Substantially all electric utility property is mortgaged under mortgage bond indentures.

(b) Duke Energy includes $98 million and $670 million of capital lease purchase accounting adjustments related to Duke Energy Progress and Duke Energy Florida, respectively, related to power purchase agreements that are not accounted for as capital leases in their respective financial statements because of grandfathering provisions in GAAP.

(c) Substantially all tax-exempt bonds are secured by first mortgage bonds or letters of credit.

(d) Includes $625 million that was classified as Long-Term Debt on the Consolidated Balance Sheets due to the existence of long-term credit facilities that backstop these commercial paper balances, along with Duke Energy’s ability and intent to refinance these balances on a long-term basis. The weighted average days to maturity for Duke Energy and Piedmont's commercial paper programs were 14 days and eight days, respectively.

(e) Progress Energy amount includes a $1 billion intercompany loan related to the sale of the International Disposal Group. See Note 2 for further discussion of the sale.

(f) Duke Energy includes $1,653 million and $197 million in purchase accounting adjustments related to Progress Energy and Piedmont, respectively.

(g) Duke Energy includes $53 million in purchase accounting adjustments primarily related to the merger with Progress Energy.

(h) Refer to Note 17 for additional information on amounts from consolidated VIEs.

	December 31, 2015
	Weighted
	Average					Duke						Duke			Duke			Duke			Duke
	Interest		Duke			Energy			Progress			Energy			Energy			Energy			Energy
(in millions)	Rate		Energy			Carolinas			Energy			Progress			Florida			Ohio			Indiana
Unsecured debt, maturing 2016 - 2073	4.68	%	$	12,960		$	1,152		$	3,850		$	—		$	150		$	765		$	740
Secured debt, maturing 2016 - 2037	2.37	%	2,361			425			479			254			225			—			—
First mortgage bonds, maturing 2016 - 2045(a)	4.74	%	18,980			6,161			9,750			5,975			3,775			750			2,319
Capital leases, maturing 2016 - 2051(b)	5.39	%	1,335			24			300			144			156			13			14
Tax-exempt bonds, maturing 2017 - 2041(c)	2.59	%	1,053			355			48			48			—			77			572
Notes payable and commercial paper(d)	0.88	%	4,258			—			—			—			—			—			—
Money pool/intercompany borrowings			—			300			1,458			359			813			128			150
Fair value hedge carrying value adjustment			6			6			—			—			—			—			—
Unamortized debt discount and premium, net(e)			1,712			(17		)	(28		)	(16		)	(8		)	(28		)	(8		)
Unamortized debt issuance costs(f)			(164		)	(39		)	(85		)	(37		)	(32		)	(4		)	(19		)
Total debt	4.15	%	$	42,501		$	8,367		$	15,772		$	6,727		$	5,079		$	1,701		$	3,768
Short-term notes payable and commercial paper			(3,633		)	—			—			—			—			—			—
Short-term money pool/intercompany borrowings			—			—			(1,308		)	(209		)	(813		)	(103		)	—
Current maturities of long-term debt(g)			(2,026		)	(356		)	(315		)	(2		)	(13		)	(106		)	(547		)
Total long-term debt(g)			$	36,842		$	8,011		$	14,149		$	6,516		$	4,253		$	1,492		$	3,221

(a) Substantially all electric utility property is mortgaged under mortgage bond indentures.

(b) Duke Energy includes $114 million and $731 million of capital lease purchase accounting adjustments related to Duke Energy Progress and Duke Energy Florida, respectively, related to power purchase agreements that are not accounted for as capital leases in their respective financial statements because of grandfathering provisions in GAAP.

(c) Substantially all tax-exempt bonds are secured by first mortgage bonds or letters of credit.

(d) Includes $625 million that was classified as Long-Term Debt on the Consolidated Balance Sheets due to the existence of long-term credit facilities that backstop these commercial paper balances, along with Duke Energy’s ability and intent to refinance these balances on a long-term basis. The weighted average days to maturity for commercial paper was 15 days.

(e) Duke Energy includes $1,798 million in purchase accounting adjustments related to the merger with Progress Energy.

(f) Duke Energy includes $59 million in purchase accounting adjustments primarily related to the merger with Progress Energy.

(g) Refer to Note 17 for additional information on amounts from consolidated VIEs.

Schedule of Maturities of Long-term Debt

The following table shows the annual maturities of long-term debt for the next five years and thereafter. Amounts presented exclude short-term notes payable and commercial paper and money pool borrowings for the Subsidiary Registrants.

	December 31, 2016
			Duke				Duke		Duke		Duke		Duke
	Duke		Energy		Progress		Energy		Energy		Energy		Energy
(in millions)	Energy(a)		Carolinas		Energy		Progress		Florida		Ohio		Indiana
2017	$	2,319	$	116	$	778	$	452	$	326	$	1	$	3
2018	3,466		1,629		559		—		561		3		3
2019	3,316		5		1,992		902		292		551		63
2020	2,112		755		469		152		319		25		653
2021	3,699		501		1,473		602		372		49		70
Thereafter	31,090		6,597		12,270		4,903		4,255		1,255		2,994
Total long-term debt, including current maturities	$	46,002	$	9,603	$	17,541	$	7,011	$	6,125	$	1,884	$	3,786

(a) Excludes $1,893 million in purchase accounting adjustments related to the Progress Energy merger and the Piedmont acquisition.

Schedule of Long-term Debt Instruments

The following tables summarize significant debt issuances (in millions).

				Year Ended December 31, 2016
						Duke		Duke		Duke		Duke		Duke		Duke
	Maturity	Interest		Duke		Energy		Energy		Energy		Energy		Energy		Energy
Issuance Date	Date	Rate		Energy		(Parent)		Carolinas		Progress		Florida		Ohio		Indiana
Unsecured Debt
April 2016(a)	April 2023	2.875	%	$	350	$	350	$	—	$	—	$	—	$	—	$	—
August 2016	September 2021	1.800	%	750		750		—		—		—		—		—
August 2016	September 2026	2.650	%	1,500		1,500		—		—		—		—		—
August 2016	September 2046	3.750	%	1,500		1,500		—		—		—		—		—
Secured Debt
June 2016(b)	March 2020	1.196	%	183		—		—		—		183		—		—
June 2016(b)	September 2022	1.731	%	150		—		—		—		150		—		—
June 2016(b)	September 2029	2.538	%	436		—		—		—		436		—		—
June 2016(b)	March 2033	2.858	%	250		—		—		—		250		—		—
June 2016(b)	September 2036	3.112	%	275		—		—		—		275		—		—
August 2016	June 2034	2.747	%	228		—		—		—		—		—		—
August 2016	June 2020	2.747	%	105		—		—		—		—		—		—
First Mortgage Bonds
March 2016(c)	March 2023	2.500	%	500		—		500		—		—		—		—
March 2016(c)	March 2046	3.875	%	500		—		500		—		—		—		—
May 2016(d)	May 2046	3.750	%	500		—		—		—		—		—		500
June 2016(c)	June 2046	3.700	%	250		—		—		—		—		250		—
September 2016(e)	October 2046	3.400	%	600		—		—		—		600		—		—
September 2016(c)	October 2046	3.700	%	450		—		—		450		—		—		—
November 2016(f)	December 2026	2.950	%	600		—		600		—		—		—		—
Total issuances				$	9,127	$	4,100	$	1,600	$	450	$	1,894	$	250	$	500

(a) Proceeds were used to pay down outstanding commercial paper and for general corporate purposes.

(b) The nuclear asset recovery bonds are sequential pay amortizing bonds. The maturity date above represents the scheduled final maturity date for the bonds.

(c) Proceeds were used to fund capital expenditures for ongoing construction, capital maintenance and for general corporate purposes.

(d) Proceeds were used to repay $325 million of unsecured debt due June 2016, $150 million of first mortgage bonds due July 2016 and for general corporate purposes.

(e) Proceeds were used to fund capital expenditures for ongoing construction, capital maintenance, to repay short-term borrowings under the intercompany money pool borrowing arrangement and for general corporate purposes.

(f) Proceeds were used to repay at maturity $350 million aggregate principal amount of certain bonds due December 2016, as well as to fund capital expenditures for ongoing construction and capital maintenance and for general corporate purposes.

				Year Ended December 31, 2015
						Duke		Duke		Duke
	Maturity	Interest		Duke		Energy		Energy		Energy
Issuance Date	Date	Rate		Energy		(Parent)		Carolinas		Progress
Unsecured Debt
November 2015(a)(b)	April 2024	3.750	%	$	400	$	400	$	—	$	—
November 2015(a)(b)	December 2045	4.800	%	600		600		—		—
First Mortgage Bonds
March 2015(c)	June 2045	3.750	%	500		—		500		—
August 2015(a)(d)	August 2025	3.250	%	500		—		—		500
August 2015(a)(d)	August 2045	4.200	%	700		—		—		700
Total issuances				$	2,700	$	1,000	$	500	$	1,200

(a) Proceeds were used to repay short-term money pool and commercial paper borrowing issued to fund a portion of the NCEMPA acquisition, see Note 2 for further information.

(b) Proceeds were used to refinance at maturity $300 million of unsecured notes at Progress Energy due January 2016.

(c) Proceeds were used to redeem at maturity $500 million of first mortgage bonds due October 2015.

(d) Proceeds were used to refinance at maturity $400 million of first mortgage bonds due December 2015.

Schedule Of Line Of Credit Facilities

	December 31, 2016
				Duke			Duke			Duke			Duke			Duke			Duke
	Duke			Energy			Energy			Energy			Energy			Energy			Energy
(in millions)	Energy(a)			(Parent)			Carolinas			Progress			Florida			Ohio			Indiana
Facility size(b)	$	8,350		$	3,400		$	1,100		$	1,000		$	950		$	450		$	600
Reduction to backstop issuances
Commercial paper(c)	(2,022		)	(977		)	(300		)	(150		)	(84		)	(31		)	(150		)
Outstanding letters of credit	(78		)	(69		)	(4		)	(2		)	(1		)	—			—
Tax-exempt bonds	(116		)	—			(35		)	—			—			—			(81		)
Coal ash set-aside	(500		)	—			(250		)	(250		)	—			—			—
Available capacity	$	5,634		$	2,354		$	511		$	598		$	865		$	419		$	369

(a) Includes amounts related to Piedmont's $850 million credit facility.

(b) Represents the sublimit of each borrower.

(c) Duke Energy issued $625 million of commercial paper and loaned the proceeds through the money pool to Duke Energy Carolinas, Duke Energy Progress, Duke Energy Ohio and Duke Energy Indiana. The balances are classified as Long-Term Debt Payable to Affiliated Companies in the Consolidated Balance Sheets.