(PurchPower) (Details) - Public Utilities Purchased Power [Member] $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($)
Duke Energy Progress [Member]
Unconditional Purchase Obligations [Abstract]
2019	$ 51
2020	52
2021	53
2022	30
2023	25
Thereafter	215
Total	$ 426
Duke Energy Progress [Member] \| Minimum [Member]
Unconditional Purchase Obligations [Abstract]
Long-term Contract for Purchase of Electric Power, Date of Contract Expiration	2022
Duke Energy Progress [Member] \| Maximum [Member]
Unconditional Purchase Obligations [Abstract]
Long-term Contract for Purchase of Electric Power, Date of Contract Expiration	2031
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased	100.00%
Duke Energy Florida [Member]
Unconditional Purchase Obligations [Abstract]
2019	$ 363
2020	380
2021	365
2022	363
2023	382
Thereafter	361
Total	$ 2,214
Duke Energy Florida [Member] \| Minimum [Member]
Unconditional Purchase Obligations [Abstract]
Long-term Contract for Purchase of Electric Power, Date of Contract Expiration	2021
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased	81.00%
Duke Energy Florida [Member] \| Maximum [Member]
Unconditional Purchase Obligations [Abstract]
Long-term Contract for Purchase of Electric Power, Date of Contract Expiration	2025
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased	100.00%
Duke Energy Ohio [Member]
Unconditional Purchase Obligations [Abstract]
2019	$ 146
2020	117
2021	53
2022	11
Total	$ 327
Duke Energy Ohio [Member] \| Minimum [Member]
Unconditional Purchase Obligations [Abstract]
Long-term Contract for Purchase of Electric Power, Date of Contract Expiration	2020
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased	1.00%
Duke Energy Ohio [Member] \| Maximum [Member]
Unconditional Purchase Obligations [Abstract]
Long-term Contract for Purchase of Electric Power, Date of Contract Expiration	2022
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased	8.00%

No definition available.

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- Definition

Share of plant output being purchased under a long-term contract to purchase electricity from a production plant constructed and financed by a public utility district, cooperative, or other organization.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.D)
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- References

No definition available.

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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