Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current Assets [Abstract]
Cash and cash equivalents	$ 2,166	$ 1,424
Short Term Investments	118	333
Receivables (net of allowance for doubtful accounts)	1,585	1,516
Restricted receivables of variable interest entities (net of allowance for doubtful accounts)	1,258	1,201
Inventory	3,100	3,223
Other	2,191	2,425
Total current assets	10,418	10,122
Investments and Other Assets [Abstract]
Investments in equity method unconsolidated affiliates	511	483
Nuclear decommissioning trust funds	4,805	4,242
Goodwill	16,345	16,365
Intangibles, net	351	372
Notes receivable	65	71
Restricted other assets of variable interest entities	52	62
Other	2,361	2,399
Total investments and other assets	24,490	23,994
Property, Plant and Equipment [Abstract]
Cost	100,682	98,833
Cost, variable interest entities	1,679	1,558
Accumulated depreciation and amortization	(33,136)	(31,969)
Generation facilities to be retired, net	59	136
Net property, plant and equipment	69,284	68,558
Regulatory Assets and Deferred Debits [Abstract]
Regulatory assets	10,220	11,004
Other	178	178
Total regulatory assets and deferred debits	10,398	11,182
Total Assets	114,590	113,856
Current Liabilities [Abstract]
Accounts payable	1,819	2,444
Notes payable and commercial paper	1,278	745
Non-recourse notes payable of variable interest entities	325	312
Taxes accrued	706	459
Interest accrued	474	448
Current maturities of long-term debt	2,307	3,110
Other	2,330	2,511
Total current liabilities	9,239	10,029
Long-term Debt	36,137	35,499
Non-recourse long-term debt of variable interest entities	1,265	852
Deferred Credits and Other Liabilities [Abstract]
Deferred income taxes	11,489	10,490
Investment tax credits	446	458
Accrued pension and other post-retirement benefit costs	1,743	2,520
Asset retirement obligations	5,341	5,169
Regulatory liabilities	5,904	5,584
Other	1,789	2,221
Total deferred credits and other liabilities	26,712	26,442
Commitments and Contingencies
Preferred Stock of Subsidiaries	0	93
Equity [Abstract]
Common stock	1	1
Additional paid-in capital	39,317	39,279
Retained earnings	2,227	1,889
Accumulated other comprehensive (loss) income	(380)	(306)
Total Common Shareholders' Equity	41,165	40,863
Noncontrolling interests	72	78
Total equity	41,237	40,941
Total Liabilities and Equity	114,590	113,856
Duke Energy Carolinas [Member]
Current Assets [Abstract]
Cash and cash equivalents	25	19
Receivables (net of allowance for doubtful accounts)	140	188
Restricted receivables of variable interest entities (net of allowance for doubtful accounts)	703	637
Receivables from affiliated companies	40	3
Notes receivable from affiliated companies	595	382
Inventory	1,033	1,062
Other	474	439
Total current assets	3,010	2,730
Investments and Other Assets [Abstract]
Nuclear decommissioning trust funds	2,673	2,354
Other	845	934
Total investments and other assets	3,518	3,288
Property, Plant and Equipment [Abstract]
Cost	34,916	34,190
Accumulated depreciation and amortization	(11,731)	(11,437)
Generation facilities to be retired, net	0	73
Net property, plant and equipment	23,185	22,826
Regulatory Assets and Deferred Debits [Abstract]
Regulatory assets	1,794	1,727
Other	45	71
Total regulatory assets and deferred debits	1,839	1,798
Total Assets	31,552	30,642
Current Liabilities [Abstract]
Accounts payable	451	599
Accounts payable to affiliated companies	235	128
Taxes accrued	156	114
Interest accrued	142	96
Current maturities of long-term debt	447	406
Other	461	490
Total current liabilities	1,892	1,833
Long-term Debt	7,692	7,735
Non-recourse long-term debt of variable interest entities	300	300
Long-term debt payable to affiliated companies	300	300
Deferred Credits and Other Liabilities [Abstract]
Deferred income taxes	5,537	5,181
Investment tax credits	211	215
Accrued pension and other post-retirement benefit costs	211	221
Asset retirement obligations	2,053	1,959
Regulatory liabilities	2,484	2,102
Other	732	924
Total deferred credits and other liabilities	11,228	10,602
Commitments and Contingencies
Equity [Abstract]
Member's equity	10,155	9,888
Accumulated other comprehensive (loss) income	(15)	(16)
Total Member's Equity	10,140	9,872
Total Liabilities and Member's Equity	31,552	30,642
Progress Energy [Member]
Current Assets [Abstract]
Cash and cash equivalents	66	231
Receivables (net of allowance for doubtful accounts)	1,020	790
Receivables from affiliated companies	3	15
Notes receivable from affiliated companies	103	0
Inventory	1,361	1,441
Other	761	766
Total current assets	3,314	3,243
Investments and Other Assets [Abstract]
Nuclear decommissioning trust funds	2,132	1,888
Goodwill	3,655	3,655
Other	531	530
Total investments and other assets	6,318	6,073
Property, Plant and Equipment [Abstract]
Cost	35,922	35,130
Cost, variable interest entities	16	16
Accumulated depreciation and amortization	(12,916)	(12,512)
Generation facilities to be retired, net	59	63
Net property, plant and equipment	23,081	22,697
Regulatory Assets and Deferred Debits [Abstract]
Regulatory assets	4,620	5,292
Other	97	100
Total regulatory assets and deferred debits	4,717	5,392
Total Assets	37,430	37,405
Current Liabilities [Abstract]
Accounts payable	770	1,066
Accounts payable to affiliated companies	55	30
Notes payable to affiliated companies	1,195	455
Taxes accrued	246	83
Interest accrued	192	192
Current maturities of long-term debt	317	843
Other	1,177	1,118
Total current liabilities	3,952	3,787
Long-term Debt	13,498	13,311
Long-term debt payable to affiliated companies	0	274
Deferred Credits and Other Liabilities [Abstract]
Deferred income taxes	2,962	2,558
Investment tax credits	89	95
Accrued pension and other post-retirement benefit costs	994	1,608
Asset retirement obligations	2,486	2,413
Regulatory liabilities	2,385	2,469
Other	397	612
Total deferred credits and other liabilities	9,313	9,755
Commitments and Contingencies
Preferred Stock of Subsidiaries	0	93
Equity [Abstract]
Common stock	0	0
Additional paid-in capital	7,465	7,465
Retained earnings	3,257	2,783
Accumulated other comprehensive (loss) income	(59)	(67)
Total Common Shareholders' Equity	10,663	10,181
Noncontrolling interests	4	4
Total equity	10,667	10,185
Total Liabilities and Equity	37,430	37,405
Duke Energy Progress [Member]
Current Assets [Abstract]
Cash and cash equivalents	32	18
Receivables (net of allowance for doubtful accounts)	553	458
Receivables from affiliated companies	1	5
Inventory	795	828
Other	407	313
Total current assets	1,788	1,622
Investments and Other Assets [Abstract]
Nuclear decommissioning trust funds	1,425	1,259
Other	297	251
Total investments and other assets	1,722	1,510
Property, Plant and Equipment [Abstract]
Cost	21,876	21,168
Cost, variable interest entities	16	16
Accumulated depreciation and amortization	(8,509)	(8,185)
Generation facilities to be retired, net	59	63
Net property, plant and equipment	13,442	13,062
Regulatory Assets and Deferred Debits [Abstract]
Regulatory assets	1,558	1,845
Other	32	29
Total regulatory assets and deferred debits	1,590	1,874
Total Assets	18,542	18,068
Current Liabilities [Abstract]
Accounts payable	399	542
Accounts payable to affiliated companies	76	76
Notes payable to affiliated companies	581	364
Taxes accrued	86	23
Interest accrued	74	69
Current maturities of long-term debt	7	407
Other	440	517
Total current liabilities	1,663	1,998
Long-term Debt	4,929	4,433
Deferred Credits and Other Liabilities [Abstract]
Deferred income taxes	2,435	2,162
Investment tax credits	87	92
Accrued pension and other post-retirement benefit costs	325	715
Asset retirement obligations	1,709	1,649
Regulatory liabilities	1,743	1,538
Other	164	295
Total deferred credits and other liabilities	6,463	6,451
Commitments and Contingencies
Preferred stock	0	59
Equity [Abstract]
Common stock	2,159	2,159
Retained earnings	3,328	2,968
Total equity	5,487	5,127
Total Liabilities and Equity	18,542	18,068
Duke Energy Florida [Member]
Current Assets [Abstract]
Cash and cash equivalents	15	131
Receivables (net of allowance for doubtful accounts)	458	318
Receivables from affiliated companies	1	20
Notes receivable from affiliated companies	30	207
Inventory	567	613
Other	325	351
Total current assets	1,396	1,640
Investments and Other Assets [Abstract]
Nuclear decommissioning trust funds	707	629
Other	176	182
Total investments and other assets	883	811
Property, Plant and Equipment [Abstract]
Cost	13,702	13,432
Accumulated depreciation and amortization	(4,188)	(4,072)
Net property, plant and equipment	9,514	9,360
Regulatory Assets and Deferred Debits [Abstract]
Regulatory assets	3,007	3,321
Other	45	48
Total regulatory assets and deferred debits	3,052	3,369
Total Assets	14,845	15,180
Current Liabilities [Abstract]
Accounts payable	336	412
Accounts payable to affiliated companies	25	44
Taxes accrued	200	48
Interest accrued	65	55
Current maturities of long-term debt	11	435
Other	667	534
Total current liabilities	1,304	1,528
Long-term Debt	4,876	4,885
Deferred Credits and Other Liabilities [Abstract]
Deferred income taxes	1,782	1,518
Accrued pension and other post-retirement benefit costs	475	610
Asset retirement obligations	777	764
Regulatory liabilities	640	787
Other	169	255
Total deferred credits and other liabilities	3,843	3,934
Commitments and Contingencies
Preferred stock	0	34
Equity [Abstract]
Common stock	1,762	1,762
Retained earnings	3,061	3,037
Accumulated other comprehensive (loss) income	(1)	0
Total equity	4,822	4,799
Total Liabilities and Equity	14,845	15,180
Duke Energy Ohio [Member]
Current Assets [Abstract]
Cash and cash equivalents	27	31
Receivables (net of allowance for doubtful accounts)	114	108
Receivables from affiliated companies	81	82
Notes receivable from affiliated companies	46	1
Inventory	198	227
Other	292	267
Total current assets	758	716
Investments and Other Assets [Abstract]
Goodwill	920	921
Intangibles, net	120	129
Other	98	75
Total investments and other assets	1,138	1,125
Property, Plant and Equipment [Abstract]
Cost	11,050	10,824
Accumulated depreciation and amortization	(2,859)	(2,698)
Net property, plant and equipment	8,191	8,126
Regulatory Assets and Deferred Debits [Abstract]
Regulatory assets	556	579
Other	14	14
Total regulatory assets and deferred debits	570	593
Total Assets	10,657	10,560
Current Liabilities [Abstract]
Accounts payable	248	318
Accounts payable to affiliated companies	66	62
Notes payable to affiliated companies	69	245
Taxes accrued	136	159
Interest accrued	28	14
Current maturities of long-term debt	5	261
Other	114	126
Total current liabilities	666	1,185
Long-term Debt	2,183	1,736
Deferred Credits and Other Liabilities [Abstract]
Deferred income taxes	1,969	1,853
Investment tax credits	6	6
Accrued pension and other post-retirement benefit costs	144	157
Asset retirement obligations	30	28
Regulatory liabilities	257	254
Other	139	175
Total deferred credits and other liabilities	2,545	2,473
Commitments and Contingencies
Equity [Abstract]
Common stock	762	762
Additional paid-in capital	4,882	4,882
Retained earnings	(381)	(477)
Accumulated other comprehensive (loss) income	0	(1)
Total equity	5,263	5,166
Total Liabilities and Equity	10,657	10,560
Duke Energy Indiana [Member]
Current Assets [Abstract]
Cash and cash equivalents	25	36
Receivables (net of allowance for doubtful accounts)	11	33
Receivables from affiliated companies	123	104
Notes receivable from affiliated companies	69	0
Inventory	413	380
Other	216	138
Total current assets	857	691
Investments and Other Assets [Abstract]
Intangibles, net	33	41
Other	160	122
Total investments and other assets	193	163
Property, Plant and Equipment [Abstract]
Cost	12,310	12,012
Accumulated depreciation and amortization	(3,839)	(3,692)
Net property, plant and equipment	8,471	8,320
Regulatory Assets and Deferred Debits [Abstract]
Regulatory assets	790	810
Other	25	24
Total regulatory assets and deferred debits	815	834
Total Assets	10,336	10,008
Current Liabilities [Abstract]
Accounts payable	114	173
Accounts payable to affiliated companies	53	60
Notes payable to affiliated companies	0	81
Taxes accrued	66	61
Interest accrued	53	53
Current maturities of long-term debt	4	405
Other	101	165
Total current liabilities	391	998
Long-term Debt	3,644	3,147
Long-term debt payable to affiliated companies	150	150
Deferred Credits and Other Liabilities [Abstract]
Deferred income taxes	1,126	853
Investment tax credits	141	142
Accrued pension and other post-retirement benefit costs	182	186
Asset retirement obligations	37	37
Regulatory liabilities	766	741
Other	42	46
Total deferred credits and other liabilities	2,294	2,005
Commitments and Contingencies
Equity [Abstract]
Common stock	1	1
Additional paid-in capital	1,384	1,384
Retained earnings	2,469	2,318
Accumulated other comprehensive (loss) income	3	5
Total equity	3,857	3,708
Total Liabilities and Equity	$ 10,336	$ 10,008