Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
CASH FLOWS FROM OPERATING ACTIVITIES [Abstract]
Net income	$ 2,831	$ 1,889	$ 2,676
Net Income (Loss) Attributable to Parent	2,816	1,883	2,665
Adjustments to reconcile net income to net cash provided by operating activities: [Abstract]
Depreciation, amortization and accretion (including amortization of nuclear fuel)	3,613	3,507	3,229
Equity component of AFUDC	(164)	(135)	(157)
FERC mitigation costs		(15)
Community support and charitable contributions expense			34
(Gains) losses on sales of other assets	(48)	(33)	(79)
Impairment charges	153	915	400
Deferred income taxes	1,244	1,149	1,264
Equity in earnings of unconsolidated affiliates	(69)	(130)	(122)
Accrued pension and other post-retirement benefit costs	71	108	307
Contributions to qualified pension plans	(302)		(250)
Payments for asset retirement obligations	(346)	(68)	(12)
(Increase) decrease in [Abstract]
Net realized and unrealized mark-to-market and hedging transactions	(29)	44	1
Receivables	359	58	(281)
Inventory	(237)	(269)	(31)
Other current assets	(65)	(414)	(35)
Increase (decrease) in [Abstract]
Accounts payable	(6)	(30)	73
Taxes accrued	(38)	(14)	77
Other current liabilities	168	(201)	24
Other assets	(216)	16	(384)
Other liabilities	(243)	209	(352)
Net cash provided by operating activities	6,676	6,586	6,382
CASH FLOWS FROM INVESTING ACTIVITIES [Abstract]
Capital expenditures	(6,766)	(5,384)	(5,526)
Investment expenditures	(263)	(90)	(81)
Acquisitions, net of cash acquired	(1,334)	(54)
Purchases of available-for-sale securities	(4,037)	(4,110)	(6,142)
Proceeds from sales and maturities of available-for-sale securities	4,040	4,133	6,315
Net proceeds from the sale of Midwest generation business and sales of equity investments and other assets	2,968	179	277
Change in Restricted Cash	191	9	167
Other	(76)	(56)	12
Net cash used in investing activities	(5,277)	(5,373)	(4,978)
CASH FLOWS FROM FINANCING ACTIVITIES [Abstract]
Proceeds from the issuance of long-term debt	2,955	2,914	3,601
Proceeds from the issuance of common stock related to employee benefit plans	17	25	9
Payments for the redemption of long-term debt	(3,029)	(3,037)	(2,761)
Payments for the redemption of preferred stock			(96)
Proceeds from issuance of short-term debt with original maturities greater than 90 days	379	1,066
Payments for the redemption of short-term debt with original maturities greater than 90 days	(931)	(564)
Notes payable and commercial paper	1,797	1,186	93
Distributions to noncontrolling interests	(9)	(65)	(15)
Contributions from noncontrolling Interests			9
Dividends paid	(2,254)	(2,234)	(2,188)
Repurchase of common shares	(1,500)
Other	(3)	31	21
Net cash provided by (used in) financing activities	(2,578)	(678)	(1,327)
Net increase (decrease) in cash and cash equivalents	(1,179)	535	77
Cash and cash equivalents at beginning of period	2,036	1,501	1,424
Cash and cash equivalents at end of period	857	2,036	1,501
Supplemental Disclosures [Abstract]
Cash paid for interest, net of amount capitalized	1,607	1,659	1,665
Cash paid for (received from) income taxes	170	158	(202)
Significant Non-cash Transactions [Abstract]
Accrued capital expenditures	771	664	594
Duke Energy Carolinas [Member]
CASH FLOWS FROM OPERATING ACTIVITIES [Abstract]
Net income	1,081	1,072
Net Income (Loss) Attributable to Parent	1,081	1,072	976
Adjustments to reconcile net income to net cash provided by operating activities: [Abstract]
Depreciation, amortization and accretion (including amortization of nuclear fuel)	1,361	1,273	1,167
Equity component of AFUDC	(96)	(91)	(91)
FERC mitigation costs		3	14
(Gains) losses on sales of other assets	1
Impairment charges	1
Deferred income taxes	397	376	534
Accrued pension and other post-retirement benefit costs	15	22	38
Contributions to qualified pension plans	(91)
Payments for asset retirement obligations	(167)
(Increase) decrease in [Abstract]
Net realized and unrealized mark-to-market and hedging transactions			(9)
Receivables	42	48	(12)
Receivables from affiliated companies	(32)		(72)
Inventory	(157)	(60)	(9)
Other current assets	(51)	(236)	(1)
Increase (decrease) in [Abstract]
Accounts payable	(4)	10	58
Accounts payable to affiliated companies	75	(7)	33
Taxes accrued	(128)	(15)	4
Other current liabilities	127	(10)	(40)
Other assets	76	17	(102)
Other liabilities	(77)	(22)	(77)
Net cash provided by operating activities	2,373	2,380	2,411
CASH FLOWS FROM INVESTING ACTIVITIES [Abstract]
Capital expenditures	(1,933)	(1,879)	(1,695)
Purchases of available-for-sale securities	(2,555)	(2,064)	(2,405)
Proceeds from sales and maturities of available-for-sale securities	2,555	2,044	2,363
Notes receivable from affiliated companies		72	160
Notes receivable from affiliated companies payments	(13)
Other	(35)	(18)	(24)
Net cash used in investing activities	(1,981)	(1,845)	(1,601)
CASH FLOWS FROM FINANCING ACTIVITIES [Abstract]
Proceeds from the issuance of long-term debt	516		100
Payments for the redemption of long-term debt	(506)	(45)	(405)
Distribution to parent	(401)	(500)	(499)
Other	(1)		(2)
Net cash provided by (used in) financing activities	(392)	(545)	(806)
Net increase (decrease) in cash and cash equivalents		(10)	4
Cash and cash equivalents at beginning of period	13	23	19
Cash and cash equivalents at end of period	13	13	23
Supplemental Disclosures [Abstract]
Cash paid for interest, net of amount capitalized	389	388	336
Cash paid for (received from) income taxes	342	305	(7)
Significant Non-cash Transactions [Abstract]
Accrued capital expenditures	239	194	199
Progress Energy [Member]
CASH FLOWS FROM OPERATING ACTIVITIES [Abstract]
Net income	1,062	874	675
Net Income (Loss) Attributable to Parent	1,051	869	672
Adjustments to reconcile net income to net cash provided by operating activities: [Abstract]
Depreciation, amortization and accretion (including amortization of nuclear fuel)	1,312	1,313	1,041
Equity component of AFUDC	(54)	(26)	(50)
FERC mitigation costs		(18)
Community support and charitable contributions expense			20
(Gains) losses on sales of other assets	(31)	(6)	2
Impairment charges	12	2	380
Deferred income taxes	714	1,014	616
Accrued pension and other post-retirement benefit costs	(5)	27	172
Contributions to qualified pension plans	(83)		(250)
Payments for asset retirement obligations	(156)	(68)	(12)
(Increase) decrease in [Abstract]
Net realized and unrealized mark-to-market and hedging transactions	(6)	12	55
Receivables	105	(31)	(148)
Receivables from affiliated companies	(316)	(56)	11
Inventory	(67)	(101)	17
Other current assets	553	(934)	(156)
Increase (decrease) in [Abstract]
Accounts payable	(193)	6	(81)
Accounts payable to affiliated companies	108	80	93
Taxes accrued	(63)	(20)	22
Other current liabilities	136	(144)	61
Other assets	(167)	(14)	(243)
Other liabilities	(112)	56	(103)
Net cash provided by operating activities	2,749	1,966	2,122
CASH FLOWS FROM INVESTING ACTIVITIES [Abstract]
Capital expenditures	(2,698)	(1,940)	(2,490)
Asset Acquisition	(1,249)
Purchases of available-for-sale securities	(1,174)	(1,689)	(2,558)
Proceeds from sales and maturities of available-for-sale securities	1,211	1,652	2,513
Proceeds from the sale of nuclear fuel	102
Notes receivable from affiliated companies	220
Notes receivable from affiliated companies payments		(145)	(75)
Other	(34)	(44)	13
Net cash used in investing activities	(3,622)	(2,166)	(2,597)
CASH FLOWS FROM FINANCING ACTIVITIES [Abstract]
Proceeds from the issuance of long-term debt	1,186	1,572	845
Payments for the redemption of long-term debt	(1,553)	(931)	(1,196)
Payments for the redemption of preferred stock			(96)
Notes payable to affiliated companies	623	(378)	758
Distributions to noncontrolling interests	(4)	(37)	(3)
Capital contribution from parent	625
Other	(2)	(42)	(6)
Net cash provided by (used in) financing activities	875	184	302
Net increase (decrease) in cash and cash equivalents	2	(16)	(173)
Cash and cash equivalents at beginning of period	42	58	231
Cash and cash equivalents at end of period	44	42	58
Supplemental Disclosures [Abstract]
Cash paid for interest, net of amount capitalized	649	664	678
Cash paid for (received from) income taxes	(426)	141	(167)
Significant Non-cash Transactions [Abstract]
Accrued capital expenditures	329	294	255
Duke Energy Progress [Member]
CASH FLOWS FROM OPERATING ACTIVITIES [Abstract]
Net income	566	467	500
Net Income (Loss) Attributable to Parent	566	467	500
Adjustments to reconcile net income to net cash provided by operating activities: [Abstract]
Depreciation, amortization and accretion (including amortization of nuclear fuel)	821	761	685
Equity component of AFUDC	(47)	(25)	(42)
FERC mitigation costs		(18)
Community support and charitable contributions expense			20
(Gains) losses on sales of other assets	(7)	(3)	(1)
Impairment charges	5		22
Deferred income taxes	354	455	368
Accrued pension and other post-retirement benefit costs	(14)	(7)	72
Contributions to qualified pension plans	(42)		(63)
Payments for asset retirement obligations	(109)
(Increase) decrease in [Abstract]
Net realized and unrealized mark-to-market and hedging transactions	(3)	13	(9)
Receivables	43	78	(88)
Receivables from affiliated companies	(6)	(8)	3
Inventory	(50)	(65)	(26)
Other current assets	185	(416)	(39)
Increase (decrease) in [Abstract]
Accounts payable	(65)	27	(18)
Accounts payable to affiliated companies	70	17	27
Taxes accrued	(34)	10	15
Other current liabilities	76	(68)	(86)
Other assets	(83)	48	(74)
Other liabilities	(66)	(21)	(78)
Net cash provided by operating activities	1,594	1,245	1,188
CASH FLOWS FROM INVESTING ACTIVITIES [Abstract]
Capital expenditures	(1,669)	(1,241)	(1,567)
Asset Acquisition	(1,249)
Purchases of available-for-sale securities	(727)	(499)	(901)
Proceeds from sales and maturities of available-for-sale securities	672	458	856
Notes receivable from affiliated companies	237
Notes receivable from affiliated companies payments		(237)
Other	(30)	(12)	4
Net cash used in investing activities	(2,766)	(1,531)	(1,608)
CASH FLOWS FROM FINANCING ACTIVITIES [Abstract]
Proceeds from the issuance of long-term debt	1,186	1,347	845
Payments for the redemption of long-term debt	(991)	(379)	(451)
Payments for the redemption of preferred stock			(62)
Notes payable to affiliated companies	359	(462)	98
Dividends to parent		(225)
Capital contribution from parent	626
Other	(2)	(7)	(7)
Net cash provided by (used in) financing activities	1,178	274	423
Net increase (decrease) in cash and cash equivalents	6	(12)	3
Cash and cash equivalents at beginning of period	9	21	18
Cash and cash equivalents at end of period	15	9	21
Supplemental Disclosures [Abstract]
Cash paid for interest, net of amount capitalized	218	220	217
Cash paid for (received from) income taxes	(197)	81	(94)
Significant Non-cash Transactions [Abstract]
Accrued capital expenditures	143	194	166
Duke Energy Florida [Member]
CASH FLOWS FROM OPERATING ACTIVITIES [Abstract]
Net income	599	548	325
Net Income (Loss) Attributable to Parent	599	548	325
Adjustments to reconcile net income to net cash provided by operating activities: [Abstract]
Depreciation, amortization and accretion (including amortization of nuclear fuel)	480	550	335
Equity component of AFUDC	(7)		(8)
(Gains) losses on sales of other assets		(1)	(1)
Impairment charges	7	2	358
Deferred income taxes	348	400	368
Accrued pension and other post-retirement benefit costs	5	29	79
Contributions to qualified pension plans	(40)		(133)
Payments for asset retirement obligations	(47)	(68)	(12)
(Increase) decrease in [Abstract]
Net realized and unrealized mark-to-market and hedging transactions	(3)	(9)	55
Receivables	61	(33)	(44)
Receivables from affiliated companies	(44)	(37)	17
Inventory	(17)	(36)	42
Other current assets	116	(269)	(109)
Increase (decrease) in [Abstract]
Accounts payable	(127)	18	(22)
Accounts payable to affiliated companies	46	32	(6)
Taxes accrued	67	(31)	18
Other current liabilities	57	(80)	159
Other assets	(84)	(59)	(154)
Other liabilities	(44)	10	(62)
Net cash provided by operating activities	1,373	966	1,205
CASH FLOWS FROM INVESTING ACTIVITIES [Abstract]
Capital expenditures	(1,029)	(699)	(915)
Asset Acquisition	(166)
Purchases of available-for-sale securities	(447)	(1,189)	(1,656)
Proceeds from sales and maturities of available-for-sale securities	538	1,195	1,658
Proceeds from the sale of nuclear fuel	102
Notes receivable from affiliated companies			207
Other	(3)	(31)
Net cash used in investing activities	(839)	(724)	(706)
CASH FLOWS FROM FINANCING ACTIVITIES [Abstract]
Proceeds from the issuance of long-term debt		225
Payments for the redemption of long-term debt	(562)	(252)	(435)
Payments for the redemption of preferred stock			(34)
Notes payable to affiliated companies	729	(97)	181
Dividends to parent	(350)	(124)	(325)
Distribution to parent	(350)
Other	(1)	(2)	(1)
Net cash provided by (used in) financing activities	(534)	(250)	(614)
Net increase (decrease) in cash and cash equivalents		(8)	(115)
Cash and cash equivalents at beginning of period	8	16	131
Cash and cash equivalents at end of period	8	8	16
Supplemental Disclosures [Abstract]
Cash paid for interest, net of amount capitalized	205	203	201
Cash paid for (received from) income taxes	(229)	59	(84)
Significant Non-cash Transactions [Abstract]
Accrued capital expenditures	186	100	88
Duke Energy Ohio [Member]
CASH FLOWS FROM OPERATING ACTIVITIES [Abstract]
Net income	172	(495)	102
Net Income (Loss) Attributable to Parent	172	(495)	102
Adjustments to reconcile net income to net cash provided by operating activities: [Abstract]
Depreciation, amortization and accretion (including amortization of nuclear fuel)	230	258	357
Equity component of AFUDC	(3)	(4)	(1)
(Gains) losses on sales of other assets	(8)	(1)	(5)
Impairment charges	40	941	5
Deferred income taxes	206	(219)	98
Accrued pension and other post-retirement benefit costs	9	8	17
Contributions to qualified pension plans	(8)
Payments for asset retirement obligations	(4)
(Increase) decrease in [Abstract]
Net realized and unrealized mark-to-market and hedging transactions	(10)	27	17
Receivables	23	(56)	(15)
Receivables from affiliated companies	23	14	(39)
Inventory		8	(3)
Other current assets		(5)	(1)
Increase (decrease) in [Abstract]
Accounts payable	(1)	27	13
Accounts payable to affiliated companies	(21)	(3)	15
Taxes accrued	(21)	(9)	1
Other current liabilities	88	27	14
Other assets	25	(4)	(6)
Other liabilities	(73)	(33)	(73)
Net cash provided by operating activities	667	481	496
CASH FLOWS FROM INVESTING ACTIVITIES [Abstract]
Capital expenditures	(399)	(322)	(434)
Net proceeds from the sale of Midwest generation business and sales of equity investments and other assets			11
Notes receivable from affiliated companies	145
Notes receivable from affiliated companies payments		(88)	(56)
Other	(15)	(12)	1
Net cash used in investing activities	(269)	(422)	(478)
CASH FLOWS FROM FINANCING ACTIVITIES [Abstract]
Proceeds from the issuance of long-term debt			450
Payments for the redemption of long-term debt	(157)	(449)	(258)
Notes payable to affiliated companies	(95)	473	(202)
Dividends to parent	(150)	(100)
Other	(2)	1	(3)
Net cash provided by (used in) financing activities	(404)	(75)	(13)
Net increase (decrease) in cash and cash equivalents	(6)	(16)	5
Cash and cash equivalents at beginning of period	20	36	31
Cash and cash equivalents at end of period	14	20	36
Supplemental Disclosures [Abstract]
Cash paid for interest, net of amount capitalized	76	76	71
Cash paid for (received from) income taxes	410	(5)	9
Significant Non-cash Transactions [Abstract]
Accrued capital expenditures	20	24	27
Distribution of membership interest of Duke Energy SAM, LLC to parent	1,912
Duke Energy Indiana [Member]
CASH FLOWS FROM OPERATING ACTIVITIES [Abstract]
Net income	316	359
Net Income (Loss) Attributable to Parent	316	359	358
Adjustments to reconcile net income to net cash provided by operating activities: [Abstract]
Depreciation, amortization and accretion (including amortization of nuclear fuel)	439	416	346
Equity component of AFUDC	(11)	(14)	(15)
(Gains) losses on sales of other assets	(1)
Impairment charges	88
Deferred income taxes	262	308	304
Accrued pension and other post-retirement benefit costs	13	16	25
Contributions to qualified pension plans	(19)
Payments for asset retirement obligations	(19)
(Increase) decrease in [Abstract]
Net realized and unrealized mark-to-market and hedging transactions			(30)
Receivables	(7)	(35)	3
Receivables from affiliated companies	44	36	(47)
Inventory	(21)	(103)	(53)
Other current assets	90	(8)	(40)
Increase (decrease) in [Abstract]
Accounts payable	33	(41)	32
Accounts payable to affiliated companies	25	2	(4)
Taxes accrued	35	(32)	(30)
Other current liabilities	26	5	(5)
Other assets	(82)	(21)	(16)
Other liabilities	(35)	17	(84)
Net cash provided by operating activities	1,176	905	744
CASH FLOWS FROM INVESTING ACTIVITIES [Abstract]
Capital expenditures	(690)	(625)	(545)
Purchases of available-for-sale securities	(9)	(20)	(11)
Proceeds from sales and maturities of available-for-sale securities	11	16	7
Net proceeds from the sale of Midwest generation business and sales of equity investments and other assets	17
Notes receivable from affiliated companies		96
Notes receivable from affiliated companies payments	(83)		(96)
Other	(17)	4	(3)
Net cash used in investing activities	(771)	(529)	(648)
CASH FLOWS FROM FINANCING ACTIVITIES [Abstract]
Proceeds from the issuance of long-term debt			498
Payments for the redemption of long-term debt	(5)	(5)	(405)
Notes payable to affiliated companies	(71)	71	(81)
Dividends to parent	(326)	(450)	(125)
Other		(1)	(4)
Net cash provided by (used in) financing activities	(402)	(385)	(117)
Net increase (decrease) in cash and cash equivalents	3	(9)	(21)
Cash and cash equivalents at beginning of period	6	15	36
Cash and cash equivalents at end of period	9	6	15
Supplemental Disclosures [Abstract]
Cash paid for interest, net of amount capitalized	175	169	194
Cash paid for (received from) income taxes	(253)	(61)	46
Significant Non-cash Transactions [Abstract]
Accrued capital expenditures	$ 64	$ 87	$ 73