Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (loss)	$ 699	$ 867
Net Income (Loss) Attributable to Parent	694	864
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	931	883
Equity component of AFUDC	(42)	(42)
Gains on sales of other assets	(9)	(16)
Impairment charges	3	43
Deferred income taxes	181	368
Equity in earnings of unconsolidated affiliates	(8)	(13)
Accrued pension and other post-retirement benefit costs	4	18
Contributions to pension plans		(132)
Payments for asset retirement obligations	(112)	(26)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	102	(47)
Receivables	121	(41)
Inventory	89	57
Other current assets	13	(63)
Increase (decrease) in
Accounts payable	(210)	(201)
Taxes accrued	40	(63)
Other current liabilities	(81)	(85)
Other assets	45	30
Other liabilities	(102)	(97)
Net cash provided by operating activities	1,664	1,440
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(1,645)	(1,411)
Investment expenditures	(59)	(14)
Acquisitions		(29)
Purchases of available-for-sale securities	(1,347)	(1,035)
Proceeds from sales and maturities of available-for-sale securities	1,362	1,069
Net proceeds from the sales of other assets	1	1
Change in restricted cash	(32)	(36)
Other	(38)	(1)
Net cash used in investing activities	(1,758)	(1,456)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	1,140	497
Proceeds from the issuance of common stock related to employee benefit plans	7	15
Payments for the redemption of long-term debt	(389)	(403)
Proceeds from issuance of short-term debt with original maturities greater than 90 days		187
Payments for the redemption of short-term debt with original maturities greater than 90 days	(92)	(643)
Notes payable and commercial paper	(66)	1,727
Distributions to noncontrolling interests	(1)
Dividends paid	(570)	(564)
Other	(14)	(15)
Net cash provided by financing activities	15	801
Net (decrease) increase in cash and cash equivalents	(79)	785
Cash and cash equivalents at beginning of period	857	2,036
Cash and cash equivalents at end of period	778	2,821
Significant non-cash transactions:
Accrued capital expenditures	576	438
Duke Energy Carolinas [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income (Loss) Attributable to Parent	271	292
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	330	324
Equity component of AFUDC	(23)	(24)
Deferred income taxes	145	113
Accrued pension and other post-retirement benefit costs	1	4
Contributions to pension plans		(42)
Payments for asset retirement obligations	(52)	(6)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	3
Receivables	2	16
Receivable from affiliated companies	33	(16)
Inventory	40	7
Other current assets	102	2
Increase (decrease) in
Accounts payable	(165)	(133)
Accounts payable to affiliated companies	21	50
Taxes accrued	52	(17)
Other current liabilities	21	(27)
Other assets	26	44
Other liabilities	(26)	(11)
Net cash provided by operating activities	781	576
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(459)	(448)
Purchases of available-for-sale securities	(785)	(643)
Proceeds from sales and maturities of available-for-sale securities	785	643
Notes receivable from affiliated companies payments	(691)	(605)
Other	(18)	4
Net cash used in investing activities	(1,168)	(1,049)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	992	496
Payments for the redemption of long-term debt	(1)
Distributions to parent	(600)
Other		(6)
Net cash provided by financing activities	391	490
Net (decrease) increase in cash and cash equivalents	4	17
Cash and cash equivalents at beginning of period	13	13
Cash and cash equivalents at end of period	17	30
Significant non-cash transactions:
Accrued capital expenditures	179	102
Progress Energy [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (loss)	212	263
Net Income (Loss) Attributable to Parent	209	260
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	342	329
Equity component of AFUDC	(14)	(14)
Gains on sales of other assets	(7)	(8)
Impairment charges	2
Deferred income taxes	182	196
Accrued pension and other post-retirement benefit costs	(6)	(1)
Contributions to pension plans		(42)
Payments for asset retirement obligations	(54)	(20)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	6	(22)
Receivables	70	(66)
Receivable from affiliated companies	295	(21)
Inventory	3	47
Other current assets	(76)	302
Increase (decrease) in
Accounts payable	9	(107)
Accounts payable to affiliated companies	(55)	83
Taxes accrued	42	47
Other current liabilities	(64)	(10)
Other assets	(46)	(21)
Other liabilities	(7)	(28)
Net cash provided by operating activities	834	907
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(750)	(563)
Purchases of available-for-sale securities	(533)	(298)
Proceeds from sales and maturities of available-for-sale securities	548	367
Proceeds from Insurance	43
Notes receivable from affiliated companies		42
Other	(15)	(20)
Net cash used in investing activities	(707)	(472)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	53
Payments for the redemption of long-term debt	(310)	(245)
Notes payable to affiliated companies	128	(185)
Distributions to noncontrolling interests	(1)
Other		(3)
Net cash provided by financing activities	(130)	(433)
Net (decrease) increase in cash and cash equivalents	(3)	2
Cash and cash equivalents at beginning of period	44	42
Cash and cash equivalents at end of period	41	44
Significant non-cash transactions:
Accrued capital expenditures	228	176
Duke Energy Progress [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income (Loss) Attributable to Parent	137	183
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	223	193
Equity component of AFUDC	(10)	(13)
Gains on sales of other assets	(2)	(1)
Deferred income taxes	100	138
Accrued pension and other post-retirement benefit costs	(8)	(4)
Contributions to pension plans		(21)
Payments for asset retirement obligations	(42)	(6)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	(1)	(4)
Receivables	18	(92)
Receivable from affiliated companies	10	6
Inventory	15	37
Other current assets	83	170
Increase (decrease) in
Accounts payable	(16)	(52)
Accounts payable to affiliated companies	(14)	63
Taxes accrued	18	14
Other current liabilities	(39)	(28)
Other assets	(17)	(2)
Other liabilities	(4)	(17)
Net cash provided by operating activities	451	564
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(379)	(338)
Purchases of available-for-sale securities	(390)	(149)
Proceeds from sales and maturities of available-for-sale securities	384	144
Notes receivable from affiliated companies		32
Other	(13)	(12)
Net cash used in investing activities	(398)	(323)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	53
Payments for the redemption of long-term debt	(8)	(243)
Notes payable to affiliated companies	(101)
Other	(1)	(1)
Net cash provided by financing activities	(57)	(244)
Net (decrease) increase in cash and cash equivalents	(4)	(3)
Cash and cash equivalents at beginning of period	15	9
Cash and cash equivalents at end of period	11	6
Significant non-cash transactions:
Accrued capital expenditures	55	82
Duke Energy Florida [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income (Loss) Attributable to Parent	110	113
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	116	136
Equity component of AFUDC	(4)	(1)
Impairment charges	2
Deferred income taxes	83	39
Accrued pension and other post-retirement benefit costs	1	1
Contributions to pension plans		(21)
Payments for asset retirement obligations	(12)	(14)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	7	(20)
Receivables	52	24
Receivable from affiliated companies	14	(20)
Inventory	(12)	10
Other current assets	(44)	143
Increase (decrease) in
Accounts payable	25	(54)
Accounts payable to affiliated companies	(40)	15
Taxes accrued	(70)	61
Other current liabilities	(14)	24
Other assets	(30)	(17)
Other liabilities	(6)	(15)
Net cash provided by operating activities	178	404
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(370)	(224)
Purchases of available-for-sale securities	(143)	(149)
Proceeds from sales and maturities of available-for-sale securities	164	223
Proceeds from Insurance	43
Other	(1)	(7)
Net cash used in investing activities	(307)	(157)
CASH FLOWS FROM FINANCING ACTIVITIES
Payments for the redemption of long-term debt	(2)	(2)
Notes payable to affiliated companies	135	108
Dividends to parent		(350)
Other		(1)
Net cash provided by financing activities	133	(245)
Net (decrease) increase in cash and cash equivalents	4	2
Cash and cash equivalents at beginning of period	8	8
Cash and cash equivalents at end of period	12	10
Significant non-cash transactions:
Accrued capital expenditures	173	94
Duke Energy Ohio [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (loss)		149
Net Income (Loss) Attributable to Parent	59	149
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	62	58
Equity component of AFUDC	(1)	(1)
Gains on sales of other assets	(1)	(6)
Impairment charges		40
Deferred income taxes	11	25
Accrued pension and other post-retirement benefit costs	1	2
Contributions to pension plans		(1)
Payments for asset retirement obligations	(1)
(Increase) decrease in
Net realized and unrealized mark-to-market and hedging transactions	2	(28)
Receivables	(18)	(8)
Receivable from affiliated companies	(9)	16
Inventory	1	(3)
Other current assets	78	80
Increase (decrease) in
Accounts payable	(1)	20
Accounts payable to affiliated companies		49
Taxes accrued	(31)	(4)
Other current liabilities	14	24
Other assets	(2)	15
Other liabilities		(74)
Net cash provided by operating activities	164	353
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(85)	(81)
Net proceeds from the sales of other assets	1
Notes receivable from affiliated companies payments	(19)
Notes receivable from affiliated companies		105
Other	(5)
Net cash used in investing activities	(108)	24
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of long-term debt	95
Payments for the redemption of long-term debt	(51)	(151)
Notes payable to affiliated companies	(95)	(193)
Other		(1)
Net cash provided by financing activities	(51)	(345)
Net (decrease) increase in cash and cash equivalents	5	32
Cash and cash equivalents at beginning of period	14	20
Cash and cash equivalents at end of period	19	52
Significant non-cash transactions:
Accrued capital expenditures	31	15
Duke Energy Indiana [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income (Loss) Attributable to Parent	95	108
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion (including amortization of nuclear fuel)	127	105
Equity component of AFUDC	(3)	(3)
Deferred income taxes	(16)	140
Accrued pension and other post-retirement benefit costs	2	3
Contributions to pension plans		(9)
Payments for asset retirement obligations	(5)
(Increase) decrease in
Receivables	16	3
Receivable from affiliated companies	7	1
Inventory	45	(5)
Other current assets	(19)	9
Increase (decrease) in
Accounts payable	(44)	21
Accounts payable to affiliated companies	(22)	1
Taxes accrued	30	13
Other current liabilities	(18)	6
Other assets	(4)	(8)
Other liabilities	(11)	(24)
Net cash provided by operating activities	180	361
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(151)	(188)
Purchases of available-for-sale securities	(5)	(3)
Proceeds from sales and maturities of available-for-sale securities	4	2
Notes receivable from affiliated companies payments	(19)	(106)
Other	(1)	16
Net cash used in investing activities	(172)	(279)
CASH FLOWS FROM FINANCING ACTIVITIES
Notes payable to affiliated companies		(71)
Other		(1)
Net cash provided by financing activities		(72)
Net (decrease) increase in cash and cash equivalents	8	10
Cash and cash equivalents at beginning of period	9	6
Cash and cash equivalents at end of period	17	16
Significant non-cash transactions:
Accrued capital expenditures	$ 42	$ 60