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Fair Value Measurements (Fair Value Measurement Amounts for Assets and Liabilities) (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | $ 3,191 |
Derivative assets | 320 | $ 61
Total assets | 11,213 | 9,748
Derivative liabilities | (472) | (324)
Net assets (liabilities) | 10,741 | 9,424
Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 3 | 1
Total assets | 8,667 | 7,551
Derivative liabilities | (13) |
Net assets (liabilities) | 8,654 | 7,551
Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 293 | 53
Total assets | 2,472 | 2,144
Derivative liabilities | (314) | (240)
Net assets (liabilities) | 2,158 | 1,904
Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 24 | 7
Total assets | 24 | 7
Derivative liabilities | (145) | (84)
Net assets (liabilities) | (121) | (77)
Not Categorized |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 50 | 46
Net assets (liabilities) | 50 | 46
NDTF |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 160 | 177
Equity securities, FV-NI | 7,350 | 6,235
Debt securities, available-for-sale | 2,891 | 2,717
NDTF | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 160 | 177
Debt securities, available-for-sale | 967 | 874
NDTF | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 1,924 | 1,843
NDTF equity securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 7,350 | 6,235
NDTF equity securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 7,300 | 6,189
NDTF equity securities | Not Categorized |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 50 | 46
Other Investments |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 156 | 146
Debt securities, available-for-sale | 300 | 285
Other Investments | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 156 | 146
Debt securities, available-for-sale | 45 | 37
Other Investments | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 255 | 248
Other cash and cash equivalents |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 36 | 127
Other cash and cash equivalents | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 36 | 127
Duke Energy Carolinas |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 1,441 |
Derivative assets | 162 | 20
Total assets | 5,921 | 4,985
Derivative liabilities | (35) | (20)
Net assets (liabilities) | 5,886 | 4,965
Duke Energy Carolinas | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 4,607 | 3,861
Net assets (liabilities) | 4,607 | 3,861
Duke Energy Carolinas | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 162 | 20
Total assets | 1,264 | 1,078
Derivative liabilities | (35) | (20)
Net assets (liabilities) | 1,229 | 1,058
Duke Energy Carolinas | Not Categorized |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 50 | 46
Net assets (liabilities) | 50 | 46
Duke Energy Carolinas | NDTF |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 53 | 30
Equity securities, FV-NI | 4,265 | 3,685
Debt securities, available-for-sale | 1,441 | 1,250
Duke Energy Carolinas | NDTF | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 53 | 30
Equity securities, FV-NI |  | 3,639
Debt securities, available-for-sale | 339 | 192
Duke Energy Carolinas | NDTF | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 1,102 | 1,058
Duke Energy Carolinas | NDTF | Not Categorized |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI |  | 46
Duke Energy Carolinas | NDTF equity securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 4,265 |
Duke Energy Carolinas | NDTF equity securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 4,215 |
Duke Energy Carolinas | NDTF equity securities | Not Categorized |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 50 |
Progress Energy |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 1,476 |
Derivative assets | 124 | 33
Total assets | 4,812 | 4,329
Derivative liabilities | (24) | (29)
Net assets (liabilities) | 4,788 | 4,300
Progress Energy | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 3,840 | 3,485
Net assets (liabilities) | 3,840 | 3,485
Progress Energy | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 124 | 33
Total assets | 972 | 844
Derivative liabilities | (24) | (29)
Net assets (liabilities) | 948 | 815
Progress Energy | NDTF |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 107 | 147
Equity securities, FV-NI | 3,085 | 2,550
Debt securities, available-for-sale | 1,450 | 1,467
Progress Energy | NDTF | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 107 | 147
Debt securities, available-for-sale | 628 | 682
Progress Energy | NDTF | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 822 | 785
Progress Energy | NDTF equity securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 3,085 | 2,550
Progress Energy | NDTF equity securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 3,085 | 2,550
Progress Energy | Other Investments |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 26 | 26
Progress Energy | Other Investments | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 26 | 26
Progress Energy | Other cash and cash equivalents |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 20 | 106
Progress Energy | Other cash and cash equivalents | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 20 | 106
Duke Energy Progress |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 1,025 |
Derivative assets | 124 | 33
Total assets | 4,229 | 3,562
Derivative liabilities | (10) | (14)
Net assets (liabilities) | 4,219 | 3,548
Duke Energy Progress | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 3,369 | 2,773
Net assets (liabilities) | 3,369 | 2,773
Duke Energy Progress | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 124 | 33
Total assets | 860 | 789
Derivative liabilities | (10) | (14)
Net assets (liabilities) | 850 | 775
Duke Energy Progress | NDTF |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 94 | 76
Equity securities, FV-NI | 2,970 | 2,459
Debt securities, available-for-sale | 1,025 | 993
Duke Energy Progress | NDTF | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 94 | 76
Debt securities, available-for-sale | 289 | 237
Duke Energy Progress | NDTF | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 736 | 756
Duke Energy Progress | NDTF equity securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 2,970 | 2,459
Duke Energy Progress | NDTF equity securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 2,970 | 2,459
Duke Energy Progress | Other cash and cash equivalents |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 16 | 1
Duke Energy Progress | Other cash and cash equivalents | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 16 | 1
Duke Energy Florida |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 451 |
Total assets | 582 | 663
Derivative liabilities | (14) |
Net assets (liabilities) | 568 | 663
Duke Energy Florida | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 470 | 608
Net assets (liabilities) | 470 | 608
Duke Energy Florida | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 112 | 55
Derivative liabilities | (14) |
Net assets (liabilities) | 98 | 55
Duke Energy Florida | NDTF |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 13 | 71
Equity securities, FV-NI | 115 | 91
Debt securities, available-for-sale | 425 | 474
Duke Energy Florida | NDTF | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 13 | 71
Debt securities, available-for-sale | 339 | 445
Duke Energy Florida | NDTF | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 86 | 29
Duke Energy Florida | NDTF equity securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 115 | 91
Duke Energy Florida | NDTF equity securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 115 | 91
Duke Energy Florida | Other Investments |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 26 | 26
Duke Energy Florida | Other Investments | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 26 | 26
Duke Energy Florida | Other cash and cash equivalents |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 3 | 1
Duke Energy Florida | Other cash and cash equivalents | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents | 3 | 1
Duke Energy Indiana |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 64 |
Derivative assets | 23 | 6
Total assets | 184 | 149
Derivative liabilities | (27) | (1)
Net assets (liabilities) | 157 | 148
Duke Energy Indiana | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 1 |
Total assets | 98 | 98
Derivative liabilities | (13) | (1)
Net assets (liabilities) | 85 | 97
Duke Energy Indiana | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 64 | 45
Derivative liabilities | (14) |
Net assets (liabilities) | 50 | 45
Duke Energy Indiana | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 22 | 6
Total assets | 22 | 6
Net assets (liabilities) | 22 | 6
Duke Energy Indiana | Other Investments |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 97 | 97
Debt securities, available-for-sale | 64 | 45
Duke Energy Indiana | Other Investments | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity securities, FV-NI | 97 | 97
Duke Energy Indiana | Other Investments | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt securities, available-for-sale | 64 | 45
Duke Energy Indiana | Other cash and cash equivalents |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents |  | 1
Duke Energy Indiana | Other cash and cash equivalents | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Cash and cash equivalents |  | 1
Piedmont |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 3 | 1
Derivative liabilities | (139) | (122)
Net assets (liabilities) | (136) | (121)
Piedmont | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 3 | 1
Net assets (liabilities) | 3 | 1
Piedmont | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative liabilities | (139) |
Net assets (liabilities) | $ (139) |
Piedmont | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative liabilities |  | (122)
Net assets (liabilities) |  | $ (122)

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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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