Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income	$ 2,190	$ 2,361
Net income (attributable to parent)	2,202	2,356
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	3,447	2,990
Equity component of AFUDC	(175)	(175)
Losses (gains) on sales of other assets	87	(28)
Impairment charges	339	216
Deferred income taxes	1,099	1,016
Equity in earnings of unconsolidated affiliates	(49)	(101)
Accrued pension and other post-retirement benefit costs	46	19
Contributions to qualified pension plans	(141)	(8)
Payments for asset retirement obligations	(389)	(420)
Payment for disposal of other assets	(105)
Other rate case adjustments	37
Provision for rate refunds	375
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	15	4
Receivables	(288)	80
Inventory	104	248
Other current assets	(648)	(210)
Increase (decrease) in
Accounts payable	389	(554)
Taxes accrued	122	233
Other current liabilities	(180)	(532)
Other assets	(585)	(159)
Other liabilities	(23)	(2)
Net cash provided by operating activities	5,667	4,978
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(6,752)	(5,841)
Contributions to equity method investments	(298)	(370)
Purchases of debt and equity securities	(2,763)	(3,170)
Proceeds from sales and maturities of debt and equity securities	2,718	3,199
Other	(175)	(149)
Net cash used in investing activities	(7,270)	(6,331)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	4,110	5,710
Proceeds from the issuance of common stock	834
Payments for the redemption of long-term debt	(2,278)	(2,035)
Proceeds from the issuance of short-term debt with original maturities greater than 90 days	243	265
Payments for the redemption of short-term debt with original maturities greater than 90 days	(207)	(237)
Notes payable and commercial paper	638	(647)
Dividends paid	(1,835)	(1,825)
Other	42	8
Net cash provided by financing activities	1,547	1,239
Net decrease in cash, cash equivalents and restricted cash	(56)	(114)
Cash, cash equivalents and restricted cash at beginning of period	505	541
Cash, cash equivalents and restricted cash at end of period	449	427
Cash and cash equivalents at beginning of period	358
Cash and cash equivalents at end of period	303
Significant non-cash transactions:
Accrued capital expenditures	1,016	740
Non-cash dividends	79
Duke Energy Carolinas [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (attributable to parent)	936	1,009
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	1,084	1,051
Equity component of AFUDC	(57)	(79)
Losses (gains) on sales of other assets	1
Impairment charges	191
Deferred income taxes	266	330
Accrued pension and other post-retirement benefit costs	3
Contributions to qualified pension plans	(46)
Payments for asset retirement obligations	(174)	(201)
Provision for rate refunds	163
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	2	1
Receivables	(154)	(40)
Receivable from affiliated companies	(63)	17
Inventory	(11)	50
Other current assets	(54)	8
Increase (decrease) in
Accounts payable	69	(78)
Accounts payable to affiliated companies	(67)	(88)
Taxes accrued	(47)	225
Other current liabilities	(129)	(149)
Other assets	18	(18)
Other liabilities	(47)	(26)
Net cash provided by operating activities	1,884	2,012
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(2,006)	(1,747)
Purchases of debt and equity securities	(1,386)	(1,660)
Proceeds from sales and maturities of debt and equity securities	1,386	1,664
Notes receivable from affiliated companies		66
Other	(103)	(58)
Net cash used in investing activities	(2,109)	(1,735)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	991
Payments for the redemption of long-term debt	(704)	(115)
Notes payable to affiliated companies	700	468
Distributions to parent	(750)	(625)
Other	(1)	(1)
Net cash provided by financing activities	236	(273)
Net increase (decrease) in cash and cash equivalents	11	4
Cash and cash equivalents at beginning of period	16	14
Cash and cash equivalents at end of period	27	18
Significant non-cash transactions:
Accrued capital expenditures	299	292
Progress Energy [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income	910	821
Net income (attributable to parent)	904	814
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	1,458	1,130
Equity component of AFUDC	(80)	(68)
Losses (gains) on sales of other assets	(23)	(20)
Impairment charges	34	137
Deferred income taxes	342	651
Accrued pension and other post-retirement benefit costs	18	(9)
Contributions to qualified pension plans	(45)
Payments for asset retirement obligations	(164)	(190)
Other rate case adjustments	37
Provision for rate refunds	101
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	14	1
Receivables	(316)	(182)
Receivable from affiliated companies	16	102
Inventory	119	126
Other current assets	(156)	(312)
Increase (decrease) in
Accounts payable	427	(281)
Accounts payable to affiliated companies	76	(59)
Taxes accrued	143	143
Other current liabilities	(28)	(184)
Other assets	(668)	(100)
Other liabilities	(34)	(85)
Net cash provided by operating activities	2,181	1,621
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(2,689)	(2,419)
Purchases of debt and equity securities	(1,216)	(1,393)
Proceeds from sales and maturities of debt and equity securities	1,225	1,411
Net proceeds from the sales of other assets	20
Notes receivable from affiliated companies	(205)	(90)
Other	(142)	(36)
Net cash used in investing activities	(3,007)	(2,527)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	1,785	1,720
Payments for the redemption of long-term debt	(719)	(611)
Notes payable to affiliated companies	(11)	(129)
Dividends to parent	(250)	(125)
Other	(3)	(3)
Net cash provided by financing activities	802	852
Net decrease in cash, cash equivalents and restricted cash	(24)	(54)
Cash, cash equivalents and restricted cash at beginning of period	87	110
Cash, cash equivalents and restricted cash at end of period	63	56
Cash and cash equivalents at beginning of period	40
Cash and cash equivalents at end of period	43
Significant non-cash transactions:
Accrued capital expenditures	441	174
Equitization of certain notes payable to affiliates		1,047
Dividend to parent related to a legal entity restructuring		547
Duke Energy Progress [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (attributable to parent)	532	547
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	869	691
Equity component of AFUDC	(41)	(35)
Losses (gains) on sales of other assets	(9)	(4)
Impairment charges	33
Deferred income taxes	187	287
Accrued pension and other post-retirement benefit costs	11	(15)
Contributions to qualified pension plans	(25)
Payments for asset retirement obligations	(133)	(149)
Other rate case adjustments	37
Provision for rate refunds	101
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	3	(2)
Receivables	(154)	(47)
Receivable from affiliated companies	(3)	(3)
Inventory	62	52
Other current assets	(239)	(34)
Increase (decrease) in
Accounts payable	325	(286)
Accounts payable to affiliated companies	73	(20)
Taxes accrued	28	33
Other current liabilities	(27)	(139)
Other assets	(358)	(49)
Other liabilities	11	(9)
Net cash provided by operating activities	1,283	818
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(1,526)	(1,247)
Purchases of debt and equity securities	(831)	(995)
Proceeds from sales and maturities of debt and equity securities	807	974
Net proceeds from the sales of other assets	20
Notes receivable from affiliated companies	(52)	64
Other	(82)	(26)
Net cash used in investing activities	(1,664)	(1,230)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	796	812
Payments for the redemption of long-term debt	(2)	(270)
Notes payable to affiliated companies	(240)
Dividends to parent	(175)	(125)
Other	(1)	(1)
Net cash provided by financing activities	378	416
Net increase (decrease) in cash and cash equivalents	(3)	4
Cash and cash equivalents at beginning of period	20	11
Cash and cash equivalents at end of period	17	15
Significant non-cash transactions:
Accrued capital expenditures	261	116
Duke Energy Florida [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (attributable to parent)	514	368
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	581	431
Equity component of AFUDC	(40)	(33)
Impairment charges	1	137
Deferred income taxes	169	366
Accrued pension and other post-retirement benefit costs	4	3
Contributions to qualified pension plans	(20)
Payments for asset retirement obligations	(31)	(41)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	7	3
Receivables	(163)	(140)
Receivable from affiliated companies	(18)	1
Inventory	57	74
Other current assets	51	(195)
Increase (decrease) in
Accounts payable	101	6
Accounts payable to affiliated companies	9	(35)
Taxes accrued	198	109
Other current liabilities	1	(45)
Other assets	(308)	(35)
Other liabilities	(58)	(71)
Net cash provided by operating activities	1,055	903
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(1,162)	(1,172)
Purchases of debt and equity securities	(385)	(398)
Proceeds from sales and maturities of debt and equity securities	418	437
Notes receivable from affiliated companies	(80)	(70)
Other	(61)	(10)
Net cash used in investing activities	(1,270)	(1,213)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	989	908
Payments for the redemption of long-term debt	(717)	(341)
Notes payable to affiliated companies		(297)
Distributions to parent	(75)
Other	(1)	(1)
Net cash provided by financing activities	196	269
Net decrease in cash, cash equivalents and restricted cash	(19)	(41)
Cash, cash equivalents and restricted cash at beginning of period	53	69
Cash, cash equivalents and restricted cash at end of period	34	28
Cash and cash equivalents at beginning of period	13
Cash and cash equivalents at end of period	20
Significant non-cash transactions:
Accrued capital expenditures	180	102
Duke Energy Ohio [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income		127
Net income (attributable to parent)	121	127
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	199	196
Equity component of AFUDC	(10)	(8)
Losses (gains) on sales of other assets	106	(1)
Impairment charges		1
Deferred income taxes	9	70
Accrued pension and other post-retirement benefit costs	3	3
Contributions to qualified pension plans		(4)
Payments for asset retirement obligations	(3)	(4)
Provision for rate refunds	23
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions		1
Receivables	(44)	3
Receivable from affiliated companies	62	48
Inventory	(2)	1
Other current assets	12	(8)
Increase (decrease) in
Accounts payable	(47)	(48)
Accounts payable to affiliated companies	(8)	(4)
Taxes accrued	(31)	(21)
Other current liabilities	19	(6)
Other assets	3	(13)
Other liabilities	(17)	(2)
Net cash provided by operating activities	395	331
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(588)	(457)
Cost of removal, net of salvage	(63)	(25)
Notes receivable from affiliated companies	14	7
Other	1
Net cash used in investing activities	(636)	(475)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt		182
Payments for the redemption of long-term debt	(3)	(2)
Notes payable to affiliated companies	239	(16)
Dividends to parent		(25)
Other		(1)
Net cash provided by financing activities	236	138
Net increase (decrease) in cash and cash equivalents	(5)	(6)
Cash and cash equivalents at beginning of period	12	13
Cash and cash equivalents at end of period	7	7
Significant non-cash transactions:
Accrued capital expenditures	83	65
Non-cash equity contribution from parent or Transfer of ownership interest of certain equity method investees to parent	106
Duke Energy Indiana [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (attributable to parent)	317	318
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	388	339
Equity component of AFUDC	(28)	(20)
Losses (gains) on sales of other assets		(1)
Impairment charges	30
Deferred income taxes	94	101
Accrued pension and other post-retirement benefit costs	5	4
Contributions to qualified pension plans	(8)
Payments for asset retirement obligations	(49)	(26)
Provision for rate refunds	58
(Increase) decrease in
Receivables	1	53
Receivable from affiliated companies	27	31
Inventory	16	54
Other current assets	(59)	18
Increase (decrease) in
Accounts payable	28	(71)
Accounts payable to affiliated companies	(6)	(1)
Taxes accrued	(51)	115
Other current liabilities	6	(18)
Other assets	29	(24)
Other liabilities	(13)	32
Net cash provided by operating activities	785	904
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(619)	(603)
Purchases of debt and equity securities	(42)	(15)
Proceeds from sales and maturities of debt and equity securities	18	6
Notes receivable from affiliated companies		57
Other	3	(40)
Net cash used in investing activities	(640)	(595)
CASH FLOWS FROM FINANCING ACTIVITIES
Payments for the redemption of long-term debt	(1)	(3)
Notes payable to affiliated companies	40
Distributions to parent	(175)	(300)
Other	(1)	(1)
Net cash provided by financing activities	(137)	(304)
Net increase (decrease) in cash and cash equivalents	8	5
Cash and cash equivalents at beginning of period	9	17
Cash and cash equivalents at end of period	17	22
Significant non-cash transactions:
Accrued capital expenditures	71	101
Piedmont Natural Gas [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (attributable to parent)	81	76
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	120	112
Impairment charges		7
Deferred income taxes	2	127
Equity in earnings of unconsolidated affiliates	(6)	(8)
Accrued pension and other post-retirement benefit costs	(3)	9
Provision for rate refunds	31
(Increase) decrease in
Receivables	192	157
Receivable from affiliated companies	(3)	(1)
Inventory	16	13
Other current assets	58	(129)
Increase (decrease) in
Accounts payable	(48)	(52)
Accounts payable to affiliated companies	14	(1)
Taxes accrued	11	(37)
Other current liabilities	8	(21)
Other assets	(4)	(9)
Other liabilities	(5)	(7)
Net cash provided by operating activities	464	236
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(497)	(407)
Cost of removal, net of salvage	(8)
Contributions to equity method investments		(12)
Notes receivable from affiliated companies	(11)
Other	3	2
Net cash used in investing activities	(513)	(417)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	100	250
Payments for the redemption of long-term debt		(35)
Notes payable and commercial paper		(330)
Notes payable to affiliated companies	(364)	284
Capital contributions from parent	300
Other		(1)
Net cash provided by financing activities	36	168
Net increase (decrease) in cash and cash equivalents	(13)	(13)
Cash and cash equivalents at beginning of period	19	25
Cash and cash equivalents at end of period	6	12
Significant non-cash transactions:
Accrued capital expenditures	$ 89	47
Non-cash equity contribution from parent or Transfer of ownership interest of certain equity method investees to parent		$ 149