Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income	$ 890	$ 893
Net income (attributable to parent)	938	900
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	1,301	1,238
Equity component of AFUDC	(40)	(31)
(Gains) Losses on sales of other assets	(1)	3
Impairment charges	2
Deferred income taxes	422	97
Equity in earnings of unconsolidated affiliates	(44)	(43)
Payments for asset retirement obligations	(132)	(152)
Provision for rate refunds	(13)	35
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions		10
Receivables	466	388
Inventory	(92)	(31)
Other current assets	(131)	98
Increase (decrease) in
Accounts payable	(657)	(636)
Taxes accrued	113	(107)
Other current liabilities	(455)	(407)
Other assets	(25)	(162)
Other liabilities	(50)	46
Net cash provided by operating activities	1,554	1,239
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(2,832)	(2,536)
Contributions to equity method investments	(77)	(94)
Purchases of debt and equity securities	(1,392)	(860)
Proceeds from sales and maturities of debt and equity securities	1,347	851
Other	(68)	(74)
Net cash used in investing activities	(3,022)	(2,713)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	1,954	2,737
Proceeds from the issuance of preferred stock		974
Proceeds from the issuance of common stock	40	13
Payments for the redemption of long-term debt	(292)	(1,201)
Proceeds from the issuance of short-term debt with original maturities greater than 90 days	1,784	135
Payments for the redemption of short-term debt with original maturities greater than 90 days	(17)	(239)
Notes payable and commercial paper	(198)	(304)
Contributions from noncontrolling interests	103	6
Dividends paid	(707)	(649)
Other	(74)	(39)
Net cash provided by financing activities	2,593	1,433
Net increase (decrease) in cash, cash equivalents and restricted cash	1,125	(41)
Cash, cash equivalents and restricted cash at beginning of period	573	591
Cash, cash equivalents and restricted cash at end of period	1,698	550
Significant non-cash transactions:
Accrued capital expenditures	934	811
Non-cash dividends	27	27
Duke Energy Carolinas
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (attributable to parent)	339	293
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	414	388
Equity component of AFUDC	(14)	(9)
(Gains) Losses on sales of other assets	(1)
Impairment charges	2
Deferred income taxes	22	64
Payments for asset retirement obligations	(41)	(65)
Provision for rate refunds		19
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions		1
Receivables	156	124
Receivable from affiliated companies	27	94
Inventory	(72)	(59)
Other current assets	96	(35)
Increase (decrease) in
Accounts payable	(253)	(266)
Accounts payable to affiliated companies	15	18
Taxes accrued	87	(91)
Other current liabilities	(108)	(70)
Other assets	(60)	(31)
Other liabilities	(11)	(7)
Net cash provided by operating activities	598	368
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(724)	(721)
Purchases of debt and equity securities	(607)	(405)
Proceeds from sales and maturities of debt and equity securities	607	405
Notes receivable from affiliated companies	(436)
Other	(18)	(9)
Net cash used in investing activities	(1,178)	(730)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	910	25
Payments for the redemption of long-term debt	(2)	(1)
Notes payable to affiliated companies	(29)	306
Distributions to parent	(300)
Other	(1)	(1)
Net cash provided by financing activities	578	329
Net increase (decrease) in cash, cash equivalents and restricted cash	(2)	(33)
Cash, cash equivalents and restricted cash at beginning of period	18	33
Cash, cash equivalents and restricted cash at end of period	16
Significant non-cash transactions:
Accrued capital expenditures	254	221
Progress Energy
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income	283	248
Net income (attributable to parent)	283	249
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	552	546
Equity component of AFUDC	(14)	(15)
(Gains) Losses on sales of other assets	1
Deferred income taxes	80	82
Payments for asset retirement obligations	(79)	(75)
Provision for rate refunds	2	6
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	1	1
Receivables	149	187
Receivable from affiliated companies	27	122
Inventory	(40)	(18)
Other current assets	43	35
Increase (decrease) in
Accounts payable	(211)	(196)
Accounts payable to affiliated companies	19	(94)
Taxes accrued	71	26
Other current liabilities	(128)	(196)
Other assets	(41)	(111)
Other liabilities	(56)	(7)
Net cash provided by operating activities	659	541
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(972)	(1,012)
Purchases of debt and equity securities	(651)	(409)
Proceeds from sales and maturities of debt and equity securities	643	405
Notes receivable from affiliated companies	164	(31)
Other	(39)	(45)
Net cash used in investing activities	(855)	(1,092)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt		1,295
Payments for the redemption of long-term debt	(283)	(1,132)
Notes payable to affiliated companies	479	370
Other	(1)	1
Net cash provided by financing activities	195	534
Net increase (decrease) in cash, cash equivalents and restricted cash	(1)	(17)
Cash, cash equivalents and restricted cash at beginning of period	126	112
Cash, cash equivalents and restricted cash at end of period	125	95
Significant non-cash transactions:
Accrued capital expenditures	310	310
Duke Energy Progress
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (attributable to parent)	204	203
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	331	336
Equity component of AFUDC	(10)	(14)
(Gains) Losses on sales of other assets	1
Deferred income taxes	43	33
Payments for asset retirement obligations	(75)	(68)
Provision for rate refunds	2	6
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	(2)	(3)
Receivables	133	87
Receivable from affiliated companies	2	(5)
Inventory	(22)	(5)
Other current assets	54	96
Increase (decrease) in
Accounts payable	(220)	(196)
Accounts payable to affiliated companies	5	(57)
Taxes accrued	26	(4)
Other current liabilities	(73)	(109)
Other assets	(51)	(47)
Other liabilities	(8)	(7)
Net cash provided by operating activities	340	246
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(466)	(548)
Purchases of debt and equity securities	(550)	(315)
Proceeds from sales and maturities of debt and equity securities	540	308
Notes receivable from affiliated companies		(38)
Other	(16)	(20)
Net cash used in investing activities	(492)	(613)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt		1,270
Payments for the redemption of long-term debt	(1)	(601)
Notes payable to affiliated companies	163	(294)
Other		(1)
Net cash provided by financing activities	162	374
Net increase (decrease) in cash, cash equivalents and restricted cash	10	7
Cash, cash equivalents and restricted cash at beginning of period	22	23
Cash, cash equivalents and restricted cash at end of period	32	30
Significant non-cash transactions:
Accrued capital expenditures	87	117
Duke Energy Florida
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (attributable to parent)	120	96
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	219	207
Equity component of AFUDC	(4)	(1)
Deferred income taxes	34	45
Payments for asset retirement obligations	(5)	(7)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	3	2
Receivables	15	55
Receivable from affiliated companies		(6)
Inventory	(19)	(13)
Other current assets	7	(35)
Increase (decrease) in
Accounts payable	11
Accounts payable to affiliated companies	(20)	(62)
Taxes accrued	31	20
Other current liabilities	(58)	(84)
Other assets	13	(63)
Other liabilities	(46)	(1)
Net cash provided by operating activities	301	153
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(506)	(422)
Purchases of debt and equity securities	(101)	(95)
Proceeds from sales and maturities of debt and equity securities	103	97
Notes receivable from affiliated companies	173
Other	(23)	(25)
Net cash used in investing activities	(354)	(445)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt		25
Payments for the redemption of long-term debt	(282)	(81)
Notes payable to affiliated companies	305	291
Other	(1)	2
Net cash provided by financing activities	22	237
Net increase (decrease) in cash, cash equivalents and restricted cash	(31)	(55)
Cash, cash equivalents and restricted cash at beginning of period	56	75
Cash, cash equivalents and restricted cash at end of period	25	20
Significant non-cash transactions:
Accrued capital expenditures	223	193
Duke Energy Ohio
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (attributable to parent)	65	69
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	69	65
Equity component of AFUDC	(1)	(3)
Deferred income taxes	14	20
Payments for asset retirement obligations		(1)
Provision for rate refunds	3	4
(Increase) decrease in
Receivables	1	5
Receivable from affiliated companies	40	35
Inventory	14	15
Other current assets	8	(6)
Increase (decrease) in
Accounts payable	(19)	(5)
Accounts payable to affiliated companies		(8)
Taxes accrued	(49)	(45)
Other current liabilities	2	14
Other assets	(2)	(10)
Other liabilities	(8)	(4)
Net cash provided by operating activities	137	145
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(217)	(233)
Notes receivable from affiliated companies		(463)
Other	(10)	(11)
Net cash used in investing activities	(227)	(707)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt		794
Notes payable to affiliated companies	87	(236)
Net cash provided by financing activities	87	558
Net increase (decrease) in cash, cash equivalents and restricted cash	(3)	(4)
Cash, cash equivalents and restricted cash at beginning of period	17	21
Cash, cash equivalents and restricted cash at end of period	14	17
Significant non-cash transactions:
Accrued capital expenditures	66	68
Duke Energy Indiana
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (attributable to parent)	99	110
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	133	132
Equity component of AFUDC	(6)	(4)
(Gains) Losses on sales of other assets		3
Deferred income taxes	16	28
Payments for asset retirement obligations	(12)	(11)
(Increase) decrease in
Receivables	15	4
Receivable from affiliated companies	3	20
Inventory	(21)	(13)
Other current assets	25	19
Increase (decrease) in
Accounts payable	(13)	8
Accounts payable to affiliated companies	(21)	(11)
Taxes accrued	43	20
Other current liabilities	(27)	(15)
Other assets	(4)	12
Other liabilities	8	6
Net cash provided by operating activities	238	308
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(210)	(208)
Purchases of debt and equity securities	(5)	(6)
Proceeds from sales and maturities of debt and equity securities	2	4
Notes receivable from affiliated companies	(543)
Other	(6)	(11)
Net cash used in investing activities	(762)	(221)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	544
Payments for the redemption of long-term debt		(60)
Notes payable to affiliated companies	(30)	(31)
Net cash provided by financing activities	514	(91)
Net increase (decrease) in cash, cash equivalents and restricted cash	(10)	(4)
Cash, cash equivalents and restricted cash at beginning of period	25	24
Cash, cash equivalents and restricted cash at end of period	15	20
Significant non-cash transactions:
Accrued capital expenditures	70	76
Piedmont Natural Gas
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (attributable to parent)	178	122
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	46	42
Equity component of AFUDC	(5)
Deferred income taxes	12	23
Equity in earnings of unconsolidated affiliates	(2)	(2)
Provision for rate refunds	(18)	7
(Increase) decrease in
Receivables	65	27
Receivable from affiliated companies	(3)	12
Inventory	33	45
Other current assets	(9)	22
Increase (decrease) in
Accounts payable	(76)	(44)
Accounts payable to affiliated companies	9	(4)
Taxes accrued	12	(49)
Other current liabilities	(12)	15
Other assets	1	(3)
Other liabilities	(1)	(5)
Net cash provided by operating activities	230	208
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(231)	(209)
Other	(5)	(2)
Net cash used in investing activities	(236)	(211)
CASH FLOWS FROM FINANCING ACTIVITIES
Notes payable to affiliated companies	10	3
Net cash provided by financing activities	10	3
Net increase (decrease) in cash, cash equivalents and restricted cash	4
Cash, cash equivalents and restricted cash at end of period	4
Significant non-cash transactions:
Accrued capital expenditures	$ 114	$ 92