Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 941	$ 890
Net income	992	938
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	1,385	1,301
Equity in losses (earnings) of unconsolidated affiliates	17	(44)
Equity component of AFUDC	(42)	(40)
Deferred income taxes	86	422
Payments for asset retirement obligations	(114)	(132)
(Increase) decrease in
Receivables	377	466
Inventory	91	(92)
Other current assets	(47)	(131)
Increase (decrease) in
Accounts payable	(467)	(657)
Taxes accrued	104	113
Other current liabilities	(263)	(455)
Other assets	51	(37)
Other liabilities	(31)	(50)
Net cash provided by operating activities	2,088	1,554
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(2,215)	(2,832)
Contributions to equity method investments		(77)
Purchases of debt and equity securities	(1,584)	(1,392)
Proceeds from sales and maturities of debt and equity securities	1,601	1,347
Disbursements to canceled equity method investments	(855)
Other	(84)	(68)
Net cash used in investing activities	(3,137)	(3,022)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	608	1,954
Proceeds from the issuance of common stock	5	40
Payments for the redemption of long-term debt	(76)	(292)
Proceeds from the issuance of short-term debt with original maturities greater than 90 days	50	1,784
Payments for the redemption of short-term debt with original maturities greater than 90 days	(909)	(17)
Notes payable and commercial paper	2,046	(198)
Contributions from noncontrolling interests	303	103
Dividends paid	(783)	(707)
Other	(59)	(74)
Net cash provided by financing activities	1,185	2,593
Net increase in cash, cash equivalents and restricted cash	136	1,125
Cash, cash equivalents and restricted cash at beginning of period	556	573
Cash, cash equivalents and restricted cash at end of period	692	1,698
Significant non-cash transactions:
Accrued capital expenditures	921	934
Non-cash dividends		27
Duke Energy Carolinas
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	312	339
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	428	414
Equity component of AFUDC	(16)	(14)
Deferred income taxes	(8)	22
Payments for asset retirement obligations	(35)	(41)
(Increase) decrease in
Receivables	156	156
Receivables from affiliated companies	5	27
Inventory	(11)	(72)
Other current assets	(48)	96
Increase (decrease) in
Accounts payable	(255)	(253)
Accounts payable to affiliated companies	7	15
Taxes accrued	62	87
Other current liabilities	(77)	(108)
Other assets	43	(60)
Other liabilities	(17)	(10)
Net cash provided by operating activities	546	598
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(622)	(724)
Purchases of debt and equity securities	(1,128)	(607)
Proceeds from sales and maturities of debt and equity securities	1,128	607
Notes receivable from affiliated companies		(436)
Other	(43)	(18)
Net cash used in investing activities	(665)	(1,178)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	142	910
Payments for the redemption of long-term debt	(33)	(2)
Notes payable to affiliated companies	2	(29)
Distributions to parent		(300)
Other	(1)	(1)
Net cash provided by financing activities	110	578
Net increase in cash, cash equivalents and restricted cash	(9)	(2)
Cash, cash equivalents and restricted cash at beginning of period	21	18
Cash, cash equivalents and restricted cash at end of period	12	16
Significant non-cash transactions:
Accrued capital expenditures	268	254
Progress Energy
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	290	283
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	575	552
Equity component of AFUDC	(13)	(14)
Deferred income taxes	79	80
Payments for asset retirement obligations	(69)	(79)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	6	1
Receivables	214	149
Receivables from affiliated companies	81	27
Inventory	39	(40)
Other current assets	(150)	43
Increase (decrease) in
Accounts payable	(69)	(211)
Accounts payable to affiliated companies	32	19
Taxes accrued	23	71
Other current liabilities	(60)	(128)
Other assets	(27)	(38)
Other liabilities	(64)	(56)
Net cash provided by operating activities	887	659
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(796)	(972)
Purchases of debt and equity securities	(517)	(651)
Proceeds from sales and maturities of debt and equity securities	537	643
Notes receivable from affiliated companies		164
Other	(59)	(39)
Net cash used in investing activities	(835)	(855)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	98
Payments for the redemption of long-term debt	(34)	(283)
Notes payable to affiliated companies	(125)	479
Other	(2)	(1)
Net cash provided by financing activities	(63)	195
Net increase in cash, cash equivalents and restricted cash	(11)	(1)
Cash, cash equivalents and restricted cash at beginning of period	200	126
Cash, cash equivalents and restricted cash at end of period	189	125
Significant non-cash transactions:
Accrued capital expenditures	317	310
Duke Energy Progress
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	210	204
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	331	331
Equity component of AFUDC	(8)	(10)
Deferred income taxes	6	43
Payments for asset retirement obligations	(46)	(75)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	2	(2)
Receivables	131	133
Receivables from affiliated companies	(20)	2
Inventory	29	(22)
Other current assets	(21)	54
Increase (decrease) in
Accounts payable	(62)	(220)
Accounts payable to affiliated companies	10	5
Taxes accrued	(12)	26
Other current liabilities	(25)	(73)
Other assets	(35)	(48)
Other liabilities	(15)	(8)
Net cash provided by operating activities	475	340
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(400)	(466)
Purchases of debt and equity securities	(382)	(550)
Proceeds from sales and maturities of debt and equity securities	380	540
Other	(29)	(16)
Net cash used in investing activities	(431)	(492)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	98
Payments for the redemption of long-term debt	(2)	(1)
Notes payable to affiliated companies	(132)	163
Other	(1)
Net cash provided by financing activities	(37)	162
Net increase in cash, cash equivalents and restricted cash	7	10
Cash, cash equivalents and restricted cash at beginning of period	39	22
Cash, cash equivalents and restricted cash at end of period	46	32
Significant non-cash transactions:
Accrued capital expenditures	96	87
Duke Energy Florida
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	117	120
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	243	219
Equity component of AFUDC	(4)	(4)
Deferred income taxes	74	34
Payments for asset retirement obligations	(24)	(5)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	2	3
Receivables	83	15
Receivables from affiliated companies	(4)
Inventory	10	(19)
Other current assets	(101)	7
Increase (decrease) in
Accounts payable	(7)	11
Accounts payable to affiliated companies	23	(20)
Taxes accrued	3	31
Other current liabilities	(41)	(58)
Other assets	12	13
Other liabilities	(48)	(46)
Net cash provided by operating activities	338	301
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(396)	(506)
Purchases of debt and equity securities	(134)	(101)
Proceeds from sales and maturities of debt and equity securities	157	103
Notes receivable from affiliated companies		173
Other	(30)	(23)
Net cash used in investing activities	(403)	(354)
CASH FLOWS FROM FINANCING ACTIVITIES
Payments for the redemption of long-term debt	(33)	(282)
Notes payable to affiliated companies	83	305
Other		(1)
Net cash provided by financing activities	50	22
Net increase in cash, cash equivalents and restricted cash	(15)	(31)
Cash, cash equivalents and restricted cash at beginning of period	50	56
Cash, cash equivalents and restricted cash at end of period	35	25
Significant non-cash transactions:
Accrued capital expenditures	222	223
Duke Energy Ohio
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	91	65
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	75	69
Equity component of AFUDC	(2)	(1)
Deferred income taxes	12	14
(Increase) decrease in
Receivables		1
Receivables from affiliated companies	5	40
Inventory	2	14
Other current assets	(5)	8
Increase (decrease) in
Accounts payable	8	(19)
Accounts payable to affiliated companies	(12)
Taxes accrued	(55)	(49)
Other current liabilities	(8)	2
Other assets	(16)	(2)
Other liabilities	1	(5)
Net cash provided by operating activities	96	137
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(220)	(217)
Notes receivable from affiliated companies	37
Other	(10)	(10)
Net cash used in investing activities	(193)	(227)
CASH FLOWS FROM FINANCING ACTIVITIES
Notes payable to affiliated companies	101	87
Net cash provided by financing activities	101	87
Net increase in cash, cash equivalents and restricted cash	4	(3)
Cash, cash equivalents and restricted cash at beginning of period	14	17
Cash, cash equivalents and restricted cash at end of period	18	14
Significant non-cash transactions:
Accrued capital expenditures	84	66
Duke Energy Indiana
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	112	99
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	153	133
Equity component of AFUDC	(5)	(6)
Deferred income taxes	(12)	16
Payments for asset retirement obligations	(10)	(12)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	1
Receivables	(9)	15
Receivables from affiliated companies		3
Inventory	38	(21)
Other current assets	(23)	25
Increase (decrease) in
Accounts payable	1	(13)
Accounts payable to affiliated companies	(16)	(21)
Taxes accrued	71	43
Other current liabilities	20	(27)
Other assets	3	(4)
Other liabilities	12	8
Net cash provided by operating activities	336	238
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(186)	(210)
Purchases of debt and equity securities	(5)	(5)
Proceeds from sales and maturities of debt and equity securities	4	2
Notes receivable from affiliated companies	(1)	(543)
Other	(7)	(6)
Net cash used in investing activities	(195)	(762)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt		544
Notes payable to affiliated companies	(131)	(30)
Net cash provided by financing activities	(131)	514
Net increase in cash, cash equivalents and restricted cash	10	(10)
Cash, cash equivalents and restricted cash at beginning of period	7	25
Cash, cash equivalents and restricted cash at end of period	17	15
Significant non-cash transactions:
Accrued capital expenditures	74	70
Piedmont
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	203	178
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	48	46
Equity in losses (earnings) of unconsolidated affiliates	(2)	(2)
Equity component of AFUDC	(6)	(5)
Deferred income taxes	(12)	12
(Increase) decrease in
Receivables	(8)	65
Receivables from affiliated companies		(3)
Inventory	31	33
Other current assets	66	(9)
Increase (decrease) in
Accounts payable	(63)	(76)
Accounts payable to affiliated companies	(21)	9
Taxes accrued	45	12
Other current liabilities	(16)	(12)
Other assets	2	1
Other liabilities	(2)	(19)
Net cash provided by operating activities	265	230
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(200)	(231)
Notes receivable from affiliated companies	(198)
Other	(8)	(5)
Net cash used in investing activities	(406)	(236)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	347
Notes payable to affiliated companies	(530)	10
Capital contributions from parent	325
Net cash provided by financing activities	142	10
Net increase in cash, cash equivalents and restricted cash	1	4
Cash, cash equivalents and restricted cash at end of period	1	4
Significant non-cash transactions:
Accrued capital expenditures	$ 106	$ 114