Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_Assets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount after tax of income (loss) from continuing operations attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.13)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4613673-111683

+ Details

Name:	us-gaap_IncomeLossFromContinuingOperations
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4J
-URI http://asc.fasb.org/extlink&oid=84234705&loc=SL4591551-111686

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=84161450&loc=SL4573702-111684

+ Details

Name:	us-gaap_NetIncomeLossAttributableToNoncontrollingInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4K
-URI http://asc.fasb.org/extlink&oid=84234705&loc=SL4591552-111686

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4569616-111683

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84161450&loc=SL4573702-111684

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4J
-URI http://asc.fasb.org/extlink&oid=84234705&loc=SL4591551-111686

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=84161450&loc=SL4573702-111684

+ Details

Name:	us-gaap_ProfitLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The total amount of operating revenues recognized during the period.

+ References

No definition available.

+ Details

Name:	us-gaap_RegulatedAndUnregulatedOperatingRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_SegmentReportingInformationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=duk_ElectricUtilitiesandInfrastructureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=duk_GasUtilitiesandInfrastructureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=duk_CommercialRenewablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=duk_TotalReportableSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=us-gaap_AllOtherSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConsolidationItemsAxis=us-gaap_IntersegmentEliminationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConsolidationItemsAxis=us-gaap_CorporateNonSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=duk_DukeEnergyOhioMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Business Segments (Business Segment Data) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Segment Reporting Information [Line Items]
Operating revenues	$ 6,135	$ 5,729
Segment income (loss)	620	716
Net Income (Loss) Attributable to Noncontrolling Interest	2	1
Net income	622	717
Segment assets	138,541		$ 137,914
Electric Utilities and Infrastructure [Member]
Segment Reporting Information [Line Items]
Operating revenues	5,315	4,939
Gas Utilities and Infrastructure [Member]
Segment Reporting Information [Line Items]
Operating revenues	702	648
Commercial Renewables [Member]
Segment Reporting Information [Line Items]
Operating revenues	101	128
Total Reportable Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues	6,118	5,715
Other Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues	17	14
Operating Segments [Member]
Segment Reporting Information [Line Items]
Segment income (loss)	886	793
Segment assets	135,682
Operating Segments [Member] \| Electric Utilities and Infrastructure [Member]
Segment Reporting Information [Line Items]
Operating revenues	5,323	4,947
Segment income (loss)	750	635
Segment assets	120,021
Operating Segments [Member] \| Gas Utilities and Infrastructure [Member]
Segment Reporting Information [Line Items]
Operating revenues	727	670
Segment income (loss)	116	133
Segment assets	11,396
Operating Segments [Member] \| Commercial Renewables [Member]
Segment Reporting Information [Line Items]
Operating revenues	101	128
Segment income (loss)	20	25
Segment assets	4,265
Operating Segments [Member] \| Total Reportable Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues	6,151	5,745
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Operating revenues	(51)	(49)
Segment assets	177
Intersegment Eliminations [Member] \| Electric Utilities and Infrastructure [Member]
Segment Reporting Information [Line Items]
Operating revenues	8	8
Intersegment Eliminations [Member] \| Gas Utilities and Infrastructure [Member]
Segment Reporting Information [Line Items]
Operating revenues	25	22
Intersegment Eliminations [Member] \| Total Reportable Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues	33	30
Intersegment Eliminations [Member] \| Other Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues	18	19
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Segment income (loss)	(266)	(77)
Segment assets	2,682
Corporate, Non-Segment [Member] \| Other Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues	35	33
Duke Energy Ohio [Member]
Segment Reporting Information [Line Items]
Operating revenues	524	518
Segment income (loss)	(25)	42
Segment assets	7,896		$ 7,875
Duke Energy Ohio [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues	510	507
Segment income (loss)	67	50
Segment assets	7,874
Duke Energy Ohio [Member] \| Operating Segments [Member] \| Electric Utilities and Infrastructure [Member]
Segment Reporting Information [Line Items]
Operating revenues	336	337
Segment income (loss)	33	24
Segment assets	5,165
Duke Energy Ohio [Member] \| Operating Segments [Member] \| Gas Utilities and Infrastructure [Member]
Segment Reporting Information [Line Items]
Operating revenues	174	170
Segment income (loss)	34	26
Segment assets	2,709
Duke Energy Ohio [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Segment assets	(3)
Duke Energy Ohio [Member] \| Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Operating revenues	14	11
Segment income (loss)	(92)	$ (8)
Segment assets	$ 25