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Investments in Debt and Equity Securities (Tables) | 6 Months Ended
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Jun. 30, 2018
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 116 |  |  | $ | — |  |  | $ | — |  |  | $ | 115 |
Equity securities | 2,837 |  |  | 40 |  |  | 4,988 |  |  | 2,805 |  |  | 27 |  |  | 4,914 |
Corporate debt securities | 5 |  |  | 12 |  |  | 560 |  |  | 17 |  |  | 2 |  |  | 570 |
Municipal bonds | 2 |  |  | 4 |  |  | 341 |  |  | 4 |  |  | 3 |  |  | 344 |
U.S. government bonds | 7 |  |  | 20 |  |  | 991 |  |  | 11 |  |  | 7 |  |  | 1,027 |
Other debt securities | — |  |  | 3 |  |  | 128 |  |  | — |  |  | 1 |  |  | 118 |
Total NDTF Investments | $ | 2,851 |  |  | $ | 79 |  |  | $ | 7,124 |  |  | $ | 2,837 |  |  | $ | 40 |  |  | $ | 7,088 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 15 |  |  | $ | — |  |  | $ | — |  |  | $ | 15 |
Equity securities | 46 |  |  | — |  |  | 109 |  |  | 59 |  |  | — |  |  | 123 |
Corporate debt securities | — |  |  | 1 |  |  | 68 |  |  | 1 |  |  | — |  |  | 57 |
Municipal bonds | 1 |  |  | 1 |  |  | 87 |  |  | 2 |  |  | 1 |  |  | 83 |
U.S. government bonds | — |  |  | 1 |  |  | 52 |  |  | — |  |  | — |  |  | 41 |
Other debt securities | — |  |  | 1 |  |  | 45 |  |  | — |  |  | 1 |  |  | 44 |
Total Other Investments | $ | 47 |  |  | $ | 4 |  |  | $ | 376 |  |  | $ | 62 |  |  | $ | 2 |  |  | $ | 363 |
Total Investments | $ | 2,898 |  |  | $ | 83 |  |  | $ | 7,500 |  |  | $ | 2,899 |  |  | $ | 42 |  |  | $ | 7,451 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 116 |  |  | $ | — |  |  | $ | — |  |  | $ | 115 |
Equity securities | 2,837 |  |  | 40 |  |  | 4,988 |  |  | 2,805 |  |  | 27 |  |  | 4,914 |
Corporate debt securities | 5 |  |  | 12 |  |  | 560 |  |  | 17 |  |  | 2 |  |  | 570 |
Municipal bonds | 2 |  |  | 4 |  |  | 341 |  |  | 4 |  |  | 3 |  |  | 344 |
U.S. government bonds | 7 |  |  | 20 |  |  | 991 |  |  | 11 |  |  | 7 |  |  | 1,027 |
Other debt securities | — |  |  | 3 |  |  | 128 |  |  | — |  |  | 1 |  |  | 118 |
Total NDTF Investments | $ | 2,851 |  |  | $ | 79 |  |  | $ | 7,124 |  |  | $ | 2,837 |  |  | $ | 40 |  |  | $ | 7,088 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 15 |  |  | $ | — |  |  | $ | — |  |  | $ | 15 |
Equity securities | 46 |  |  | — |  |  | 109 |  |  | 59 |  |  | — |  |  | 123 |
Corporate debt securities | — |  |  | 1 |  |  | 68 |  |  | 1 |  |  | — |  |  | 57 |
Municipal bonds | 1 |  |  | 1 |  |  | 87 |  |  | 2 |  |  | 1 |  |  | 83 |
U.S. government bonds | — |  |  | 1 |  |  | 52 |  |  | — |  |  | — |  |  | 41 |
Other debt securities | — |  |  | 1 |  |  | 45 |  |  | — |  |  | 1 |  |  | 44 |
Total Other Investments | $ | 47 |  |  | $ | 4 |  |  | $ | 376 |  |  | $ | 62 |  |  | $ | 2 |  |  | $ | 363 |
Total Investments | $ | 2,898 |  |  | $ | 83 |  |  | $ | 7,500 |  |  | $ | 2,899 |  |  | $ | 42 |  |  | $ | 7,451 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Available-for-sale Securities | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 116 |  |  | $ | — |  |  | $ | — |  |  | $ | 115 |
Equity securities | 2,837 |  |  | 40 |  |  | 4,988 |  |  | 2,805 |  |  | 27 |  |  | 4,914 |
Corporate debt securities | 5 |  |  | 12 |  |  | 560 |  |  | 17 |  |  | 2 |  |  | 570 |
Municipal bonds | 2 |  |  | 4 |  |  | 341 |  |  | 4 |  |  | 3 |  |  | 344 |
U.S. government bonds | 7 |  |  | 20 |  |  | 991 |  |  | 11 |  |  | 7 |  |  | 1,027 |
Other debt securities | — |  |  | 3 |  |  | 128 |  |  | — |  |  | 1 |  |  | 118 |
Total NDTF Investments | $ | 2,851 |  |  | $ | 79 |  |  | $ | 7,124 |  |  | $ | 2,837 |  |  | $ | 40 |  |  | $ | 7,088 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 15 |  |  | $ | — |  |  | $ | — |  |  | $ | 15 |
Equity securities | 46 |  |  | — |  |  | 109 |  |  | 59 |  |  | — |  |  | 123 |
Corporate debt securities | — |  |  | 1 |  |  | 68 |  |  | 1 |  |  | — |  |  | 57 |
Municipal bonds | 1 |  |  | 1 |  |  | 87 |  |  | 2 |  |  | 1 |  |  | 83 |
U.S. government bonds | — |  |  | 1 |  |  | 52 |  |  | — |  |  | — |  |  | 41 |
Other debt securities | — |  |  | 1 |  |  | 45 |  |  | — |  |  | 1 |  |  | 44 |
Total Other Investments | $ | 47 |  |  | $ | 4 |  |  | $ | 376 |  |  | $ | 62 |  |  | $ | 2 |  |  | $ | 363 |
Total Investments | $ | 2,898 |  |  | $ | 83 |  |  | $ | 7,500 |  |  | $ | 2,899 |  |  | $ | 42 |  |  | $ | 7,451 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Investments Classified by Contractual Maturity Date | The table below summarizes the maturity date for debt securities.
(in millions) | June 30, 2018 |
Due in one year or less | $ | 89 |
Due after one through five years | 518 |
Due after five through 10 years | 543 |
Due after 10 years | 1,122 |
Total | $ | 2,272 |
Schedule of Realized Gain (Loss) | Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and six months ended June 30, 2018, and from sales of AFS securities for the three and six months ended June 30, 2017, were as follows.
| Three Months Ended |  | Six Months Ended
(in millions) | June 30, 2018 |  | June 30, 2018
FV-NI: |  |  |
Realized gains | $ | 47 |  |  | $ | 66 |
Realized losses | 31 |  |  | 44 |
AFS: |  |  |
Realized gains | 5 |  |  | 10 |
Realized losses | 12 |  |  | 25 |
| Three Months Ended |  | Six Months Ended
(in millions) | June 30, 2017 |  | June 30, 2017
Realized gains | $ | 40 |  |  | $ | 133 |
Realized losses | 37 |  |  | 99 |
Duke Energy Carolinas [Member] |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 32 |  |  | $ | — |  |  | $ | — |  |  | $ | 32 |
Equity securities | 1,544 |  |  | 23 |  |  | 2,732 |  |  | 1,531 |  |  | 12 |  |  | 2,692 |
Corporate debt securities | 2 |  |  | 8 |  |  | 347 |  |  | 9 |  |  | 2 |  |  | 359 |
Municipal bonds | 1 |  |  | 1 |  |  | 72 |  |  | — |  |  | 1 |  |  | 60 |
U.S. government bonds | 2 |  |  | 12 |  |  | 474 |  |  | 3 |  |  | 4 |  |  | 503 |
Other debt securities | — |  |  | 3 |  |  | 124 |  |  | — |  |  | 1 |  |  | 112 |
Total NDTF Investments | $ | 1,549 |  |  | $ | 47 |  |  | $ | 3,781 |  |  | $ | 1,543 |  |  | $ | 20 |  |  | $ | 3,758 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 32 |  |  | $ | — |  |  | $ | — |  |  | $ | 32 |
Equity securities | 1,544 |  |  | 23 |  |  | 2,732 |  |  | 1,531 |  |  | 12 |  |  | 2,692 |
Corporate debt securities | 2 |  |  | 8 |  |  | 347 |  |  | 9 |  |  | 2 |  |  | 359 |
Municipal bonds | 1 |  |  | 1 |  |  | 72 |  |  | — |  |  | 1 |  |  | 60 |
U.S. government bonds | 2 |  |  | 12 |  |  | 474 |  |  | 3 |  |  | 4 |  |  | 503 |
Other debt securities | — |  |  | 3 |  |  | 124 |  |  | — |  |  | 1 |  |  | 112 |
Total NDTF Investments | $ | 1,549 |  |  | $ | 47 |  |  | $ | 3,781 |  |  | $ | 1,543 |  |  | $ | 20 |  |  | $ | 3,758 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Available-for-sale Securities | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 32 |  |  | $ | — |  |  | $ | — |  |  | $ | 32 |
Equity securities | 1,544 |  |  | 23 |  |  | 2,732 |  |  | 1,531 |  |  | 12 |  |  | 2,692 |
Corporate debt securities | 2 |  |  | 8 |  |  | 347 |  |  | 9 |  |  | 2 |  |  | 359 |
Municipal bonds | 1 |  |  | 1 |  |  | 72 |  |  | — |  |  | 1 |  |  | 60 |
U.S. government bonds | 2 |  |  | 12 |  |  | 474 |  |  | 3 |  |  | 4 |  |  | 503 |
Other debt securities | — |  |  | 3 |  |  | 124 |  |  | — |  |  | 1 |  |  | 112 |
Total NDTF Investments | $ | 1,549 |  |  | $ | 47 |  |  | $ | 3,781 |  |  | $ | 1,543 |  |  | $ | 20 |  |  | $ | 3,758 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Investments Classified by Contractual Maturity Date | The table below summarizes the maturity date for debt securities.
(in millions) | June 30, 2018 |
Due in one year or less | $ | 12 |
Due after one through five years | 163 |
Due after five through 10 years | 286 |
Due after 10 years | 556 |
Total | $ | 1,017 |
Schedule of Realized Gain (Loss) | Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and six months ended June 30, 2018, and from sales of AFS securities for the three and six months ended June 30, 2017, were as follows.
| Three Months Ended |  | Six Months Ended
(in millions) | June 30, 2018 |  | June 30, 2018
FV-NI: |  |  |
Realized gains | $ | 26 |  |  | $ | 36 |
Realized losses | 17 |  |  | 22 |
AFS: |  |  |
Realized gains | 4 |  |  | 9 |
Realized losses | 8 |  |  | 18 |
| Three Months Ended |  | Six Months Ended
(in millions) | June 30, 2017 |  | June 30, 2017
Realized gains | $ | 24 |  |  | $ | 90 |
Realized losses | 23 |  |  | 63 |
Progress Energy [Member] |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 84 |  |  | $ | — |  |  | $ | — |  |  | $ | 83 |
Equity securities | 1,293 |  |  | 17 |  |  | 2,256 |  |  | 1,274 |  |  | 15 |  |  | 2,222 |
Corporate debt securities | 3 |  |  | 4 |  |  | 213 |  |  | 8 |  |  | — |  |  | 211 |
Municipal bonds | 1 |  |  | 3 |  |  | 269 |  |  | 4 |  |  | 2 |  |  | 284 |
U.S. government bonds | 5 |  |  | 8 |  |  | 517 |  |  | 8 |  |  | 3 |  |  | 524 |
Other debt securities | — |  |  | — |  |  | 4 |  |  | — |  |  | — |  |  | 6 |
Total NDTF Investments | $ | 1,302 |  |  | $ | 32 |  |  | $ | 3,343 |  |  | $ | 1,294 |  |  | $ | 20 |  |  | $ | 3,330 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 11 |  |  | $ | — |  |  | $ | — |  |  | $ | 12 |
Municipal bonds | 1 |  |  | — |  |  | 47 |  |  | 2 |  |  | — |  |  | 47 |
Total Other Investments | $ | 1 |  |  | $ | — |  |  | $ | 58 |  |  | $ | 2 |  |  | $ | — |  |  | $ | 59 |
Total Investments | $ | 1,303 |  |  | $ | 32 |  |  | $ | 3,401 |  |  | $ | 1,296 |  |  | $ | 20 |  |  | $ | 3,389 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 84 |  |  | $ | — |  |  | $ | — |  |  | $ | 83 |
Equity securities | 1,293 |  |  | 17 |  |  | 2,256 |  |  | 1,274 |  |  | 15 |  |  | 2,222 |
Corporate debt securities | 3 |  |  | 4 |  |  | 213 |  |  | 8 |  |  | — |  |  | 211 |
Municipal bonds | 1 |  |  | 3 |  |  | 269 |  |  | 4 |  |  | 2 |  |  | 284 |
U.S. government bonds | 5 |  |  | 8 |  |  | 517 |  |  | 8 |  |  | 3 |  |  | 524 |
Other debt securities | — |  |  | — |  |  | 4 |  |  | — |  |  | — |  |  | 6 |
Total NDTF Investments | $ | 1,302 |  |  | $ | 32 |  |  | $ | 3,343 |  |  | $ | 1,294 |  |  | $ | 20 |  |  | $ | 3,330 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 11 |  |  | $ | — |  |  | $ | — |  |  | $ | 12 |
Municipal bonds | 1 |  |  | — |  |  | 47 |  |  | 2 |  |  | — |  |  | 47 |
Total Other Investments | $ | 1 |  |  | $ | — |  |  | $ | 58 |  |  | $ | 2 |  |  | $ | — |  |  | $ | 59 |
Total Investments | $ | 1,303 |  |  | $ | 32 |  |  | $ | 3,401 |  |  | $ | 1,296 |  |  | $ | 20 |  |  | $ | 3,389 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Available-for-sale Securities | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 84 |  |  | $ | — |  |  | $ | — |  |  | $ | 83 |
Equity securities | 1,293 |  |  | 17 |  |  | 2,256 |  |  | 1,274 |  |  | 15 |  |  | 2,222 |
Corporate debt securities | 3 |  |  | 4 |  |  | 213 |  |  | 8 |  |  | — |  |  | 211 |
Municipal bonds | 1 |  |  | 3 |  |  | 269 |  |  | 4 |  |  | 2 |  |  | 284 |
U.S. government bonds | 5 |  |  | 8 |  |  | 517 |  |  | 8 |  |  | 3 |  |  | 524 |
Other debt securities | — |  |  | — |  |  | 4 |  |  | — |  |  | — |  |  | 6 |
Total NDTF Investments | $ | 1,302 |  |  | $ | 32 |  |  | $ | 3,343 |  |  | $ | 1,294 |  |  | $ | 20 |  |  | $ | 3,330 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 11 |  |  | $ | — |  |  | $ | — |  |  | $ | 12 |
Municipal bonds | 1 |  |  | — |  |  | 47 |  |  | 2 |  |  | — |  |  | 47 |
Total Other Investments | $ | 1 |  |  | $ | — |  |  | $ | 58 |  |  | $ | 2 |  |  | $ | — |  |  | $ | 59 |
Total Investments | $ | 1,303 |  |  | $ | 32 |  |  | $ | 3,401 |  |  | $ | 1,296 |  |  | $ | 20 |  |  | $ | 3,389 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Investments Classified by Contractual Maturity Date | The table below summarizes the maturity date for debt securities.
(in millions) | June 30, 2018 |
Due in one year or less | $ | 69 |
Due after one through five years | 286 |
Due after five through 10 years | 207 |
Due after 10 years | 488 |
Total | $ | 1,050 |
Schedule of Realized Gain (Loss) | Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and six months ended June 30, 2018, and from sales of AFS securities for the three and six months ended June 30, 2017, were as follows.
| Three Months Ended | Six Months Ended
(in millions) | June 30, 2018 |  | June 30, 2018
FV-NI: |  |  |
Realized gains | $ | 21 |  |  | $ | 30 |
Realized losses | 14 |  |  | 22 |
AFS: |  |  |
Realized gains | 1 |  |  | 1 |
Realized losses | 4 |  |  | 7 |
| Three Months Ended |  | Six Months Ended
(in millions) | June 30, 2017 |  | June 30, 2017
Realized gains | $ | 15 |  |  | $ | 42 |
Realized losses | 14 |  |  | 35 |
Duke Energy Progress [Member] |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 46 |  |  | $ | — |  |  | $ | — |  |  | $ | 50 |
Equity securities | 995 |  |  | 13 |  |  | 1,819 |  |  | 980 |  |  | 12 |  |  | 1,795 |
Corporate debt securities | 2 |  |  | 3 |  |  | 153 |  |  | 6 |  |  | — |  |  | 149 |
Municipal bonds | 1 |  |  | 3 |  |  | 268 |  |  | 4 |  |  | 2 |  |  | 283 |
U.S. government bonds | 4 |  |  | 6 |  |  | 339 |  |  | 5 |  |  | 2 |  |  | 310 |
Other debt securities | — |  |  | — |  |  | 2 |  |  | — |  |  | — |  |  | 4 |
Total NDTF Investments | $ | 1,002 |  |  | $ | 25 |  |  | $ | 2,627 |  |  | $ | 995 |  |  | $ | 16 |  |  | $ | 2,591 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |
Total Other Investments | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |
Total Investments | $ | 1,002 |  |  | $ | 25 |  |  | $ | 2,628 |  |  | $ | 995 |  |  | $ | 16 |  |  | $ | 2,592 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 46 |  |  | $ | — |  |  | $ | — |  |  | $ | 50 |
Equity securities | 995 |  |  | 13 |  |  | 1,819 |  |  | 980 |  |  | 12 |  |  | 1,795 |
Corporate debt securities | 2 |  |  | 3 |  |  | 153 |  |  | 6 |  |  | — |  |  | 149 |
Municipal bonds | 1 |  |  | 3 |  |  | 268 |  |  | 4 |  |  | 2 |  |  | 283 |
U.S. government bonds | 4 |  |  | 6 |  |  | 339 |  |  | 5 |  |  | 2 |  |  | 310 |
Other debt securities | — |  |  | — |  |  | 2 |  |  | — |  |  | — |  |  | 4 |
Total NDTF Investments | $ | 1,002 |  |  | $ | 25 |  |  | $ | 2,627 |  |  | $ | 995 |  |  | $ | 16 |  |  | $ | 2,591 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |
Total Other Investments | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |
Total Investments | $ | 1,002 |  |  | $ | 25 |  |  | $ | 2,628 |  |  | $ | 995 |  |  | $ | 16 |  |  | $ | 2,592 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Available-for-sale Securities | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 46 |  |  | $ | — |  |  | $ | — |  |  | $ | 50 |
Equity securities | 995 |  |  | 13 |  |  | 1,819 |  |  | 980 |  |  | 12 |  |  | 1,795 |
Corporate debt securities | 2 |  |  | 3 |  |  | 153 |  |  | 6 |  |  | — |  |  | 149 |
Municipal bonds | 1 |  |  | 3 |  |  | 268 |  |  | 4 |  |  | 2 |  |  | 283 |
U.S. government bonds | 4 |  |  | 6 |  |  | 339 |  |  | 5 |  |  | 2 |  |  | 310 |
Other debt securities | — |  |  | — |  |  | 2 |  |  | — |  |  | — |  |  | 4 |
Total NDTF Investments | $ | 1,002 |  |  | $ | 25 |  |  | $ | 2,627 |  |  | $ | 995 |  |  | $ | 16 |  |  | $ | 2,591 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |
Total Other Investments | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |
Total Investments | $ | 1,002 |  |  | $ | 25 |  |  | $ | 2,628 |  |  | $ | 995 |  |  | $ | 16 |  |  | $ | 2,592 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Investments Classified by Contractual Maturity Date | The table below summarizes the maturity date for debt securities.
(in millions) | June 30, 2018 |
Due in one year or less | $ | 24 |
Due after one through five years | 214 |
Due after five through 10 years | 150 |
Due after 10 years | 374 |
Total | $ | 762 |
Schedule of Realized Gain (Loss) | Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and six months ended June 30, 2018, and from sales of AFS securities for the three and six months ended June 30, 2017, were as follows.
| Three Months Ended | Six Months Ended
(in millions) | June 30, 2018 |  | June 30, 2018
FV-NI: |  |  |
Realized gains | $ | 17 |  |  | $ | 25 |
Realized losses | 12 |  |  | 20 |
AFS: |  |  |
Realized gains | 1 |  |  | 1 |
Realized losses | 3 |  |  | 5 |
| Three Months Ended |  | Six Months Ended
(in millions) | June 30, 2017 |  | June 30, 2017
Realized gains | $ | 11 |  |  | $ | 35 |
Realized losses | 11 |  |  | 30 |
Duke Energy Florida [Member] |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 38 |  |  | $ | — |  |  | $ | — |  |  | $ | 33 |
Equity securities | 298 |  |  | 4 |  |  | 437 |  |  | 294 |  |  | 3 |  |  | 427 |
Corporate debt securities | 1 |  |  | 1 |  |  | 60 |  |  | 2 |  |  | — |  |  | 62 |
Municipal bonds | — |  |  | — |  |  | 1 |  |  | — |  |  | — |  |  | 1 |
U.S. government bonds | 1 |  |  | 2 |  |  | 178 |  |  | 3 |  |  | 1 |  |  | 214 |
Other debt securities | — |  |  | — |  |  | 2 |  |  | — |  |  | — |  |  | 2 |
Total NDTF Investments(b) | $ | 300 |  |  | $ | 7 |  |  | $ | 716 |  |  | $ | 299 |  |  | $ | 4 |  |  | $ | 739 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |
Municipal bonds | 1 |  |  | — |  |  | 47 |  |  | 2 |  |  | — |  |  | 47 |
Total Other Investments | $ | 1 |  |  | $ | — |  |  | $ | 48 |  |  | $ | 2 |  |  | $ | — |  |  | $ | 48 |
Total Investments | $ | 301 |  |  | $ | 7 |  |  | $ | 764 |  |  | $ | 301 |  |  | $ | 4 |  |  | $ | 787 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
(b) | During the six months ended June 30, 2018, Duke Energy Florida continued to receive reimbursements from the NDTF for costs related to ongoing decommissioning activity of the Crystal River Unit 3 nuclear plant.
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 38 |  |  | $ | — |  |  | $ | — |  |  | $ | 33 |
Equity securities | 298 |  |  | 4 |  |  | 437 |  |  | 294 |  |  | 3 |  |  | 427 |
Corporate debt securities | 1 |  |  | 1 |  |  | 60 |  |  | 2 |  |  | — |  |  | 62 |
Municipal bonds | — |  |  | — |  |  | 1 |  |  | — |  |  | — |  |  | 1 |
U.S. government bonds | 1 |  |  | 2 |  |  | 178 |  |  | 3 |  |  | 1 |  |  | 214 |
Other debt securities | — |  |  | — |  |  | 2 |  |  | — |  |  | — |  |  | 2 |
Total NDTF Investments(b) | $ | 300 |  |  | $ | 7 |  |  | $ | 716 |  |  | $ | 299 |  |  | $ | 4 |  |  | $ | 739 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |
Municipal bonds | 1 |  |  | — |  |  | 47 |  |  | 2 |  |  | — |  |  | 47 |
Total Other Investments | $ | 1 |  |  | $ | — |  |  | $ | 48 |  |  | $ | 2 |  |  | $ | — |  |  | $ | 48 |
Total Investments | $ | 301 |  |  | $ | 7 |  |  | $ | 764 |  |  | $ | 301 |  |  | $ | 4 |  |  | $ | 787 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
(b) | During the six months ended June 30, 2018, Duke Energy Florida continued to receive reimbursements from the NDTF for costs related to ongoing decommissioning activity of the Crystal River Unit 3 nuclear plant.
Available-for-sale Securities | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 38 |  |  | $ | — |  |  | $ | — |  |  | $ | 33 |
Equity securities | 298 |  |  | 4 |  |  | 437 |  |  | 294 |  |  | 3 |  |  | 427 |
Corporate debt securities | 1 |  |  | 1 |  |  | 60 |  |  | 2 |  |  | — |  |  | 62 |
Municipal bonds | — |  |  | — |  |  | 1 |  |  | — |  |  | — |  |  | 1 |
U.S. government bonds | 1 |  |  | 2 |  |  | 178 |  |  | 3 |  |  | 1 |  |  | 214 |
Other debt securities | — |  |  | — |  |  | 2 |  |  | — |  |  | — |  |  | 2 |
Total NDTF Investments(b) | $ | 300 |  |  | $ | 7 |  |  | $ | 716 |  |  | $ | 299 |  |  | $ | 4 |  |  | $ | 739 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |
Municipal bonds | 1 |  |  | — |  |  | 47 |  |  | 2 |  |  | — |  |  | 47 |
Total Other Investments | $ | 1 |  |  | $ | — |  |  | $ | 48 |  |  | $ | 2 |  |  | $ | — |  |  | $ | 48 |
Total Investments | $ | 301 |  |  | $ | 7 |  |  | $ | 764 |  |  | $ | 301 |  |  | $ | 4 |  |  | $ | 787 |
(a) | Where regulatory accounting is applied, realized and unrealized gains and losses are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
(b) | During the six months ended June 30, 2018, Duke Energy Florida continued to receive reimbursements from the NDTF for costs related to ongoing decommissioning activity of the Crystal River Unit 3 nuclear plant.
Investments Classified by Contractual Maturity Date | The table below summarizes the maturity date for debt securities.
(in millions) | June 30, 2018 |
Due in one year or less | $ | 45 |
Due after one through five years | 72 |
Due after five through 10 years | 57 |
Due after 10 years | 114 |
Total | $ | 288 |
Schedule of Realized Gain (Loss) | Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and six months ended June 30, 2018, and from sales of AFS securities for the three and six months ended June 30, 2017, were as follows.
| Three Months Ended | Six Months Ended
(in millions) | June 30, 2018 |  | June 30, 2018
FV-NI: |  |  |
Realized gains | $ | 4 |  |  | $ | 5 |
Realized losses | 2 |  |  | 2 |
AFS: |  |  |
Realized gains | — |  |  | — |
Realized losses | 1 |  |  | 2 |
| Three Months Ended | Six Months Ended
(in millions) | June 30, 2017 |  | June 30, 2017
Realized gains | $ | 4 |  |  | $ | 7 |
Realized losses | 3 |  |  | 5 |
Duke Energy Indiana [Member] |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are measured at FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
Investments |  |  |  |  |  |  |  |  |  |  |
Equity securities | $ | 36 |  |  | $ | — |  |  | $ | 74 |  |  | $ | 49 |  |  | $ | — |  |  | $ | 97 |
Corporate debt securities | — |  |  | — |  |  | 8 |  |  | — |  |  | — |  |  | 3 |
Municipal bonds | — |  |  | 1 |  |  | 33 |  |  | — |  |  | 1 |  |  | 28 |
Total Investments | $ | 36 |  |  | $ | 1 |  |  | $ | 115 |  |  | $ | 49 |  |  | $ | 1 |  |  | $ | 128 |
(a) | Realized and unrealized gains and losses where regulatory accounting is applied are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are measured at FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
Investments |  |  |  |  |  |  |  |  |  |  |
Equity securities | $ | 36 |  |  | $ | — |  |  | $ | 74 |  |  | $ | 49 |  |  | $ | — |  |  | $ | 97 |
Corporate debt securities | — |  |  | — |  |  | 8 |  |  | — |  |  | — |  |  | 3 |
Municipal bonds | — |  |  | 1 |  |  | 33 |  |  | — |  |  | 1 |  |  | 28 |
Total Investments | $ | 36 |  |  | $ | 1 |  |  | $ | 115 |  |  | $ | 49 |  |  | $ | 1 |  |  | $ | 128 |
(a) | Realized and unrealized gains and losses where regulatory accounting is applied are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Available-for-sale Securities | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are measured at FV-NI and debt investments are classified as AFS.
| June 30, 2018(a) |  | December 31, 2017
| Gross |  |  | Gross |  |  |  |  | Gross |  |  | Gross |  |  |
| Unrealized |  |  | Unrealized |  |  | Estimated |  |  | Unrealized |  |  | Unrealized |  |  | Estimated |
| Holding |  |  | Holding |  |  | Fair |  |  | Holding |  |  | Holding |  |  | Fair |
(in millions) | Gains |  |  | Losses |  |  | Value |  |  | Gains |  |  | Losses |  |  | Value |
Investments |  |  |  |  |  |  |  |  |  |  |
Equity securities | $ | 36 |  |  | $ | — |  |  | $ | 74 |  |  | $ | 49 |  |  | $ | — |  |  | $ | 97 |
Corporate debt securities | — |  |  | — |  |  | 8 |  |  | — |  |  | — |  |  | 3 |
Municipal bonds | — |  |  | 1 |  |  | 33 |  |  | — |  |  | 1 |  |  | 28 |
Total Investments | $ | 36 |  |  | $ | 1 |  |  | $ | 115 |  |  | $ | 49 |  |  | $ | 1 |  |  | $ | 128 |
(a) | Realized and unrealized gains and losses where regulatory accounting is applied are deferred as regulatory assets or liabilities, and there is no impact to net income or other comprehensive income until the gain or loss is amortized or collected.
Investments Classified by Contractual Maturity Date | The table below summarizes the maturity date for debt securities.
(in millions) | June 30, 2018 |
Due in one year or less | $ | 3 |
Due after one through five years | 20 |
Due after five through 10 years | 4 |
Due after 10 years | 14 |
Total | $ | 41 |

X
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- 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
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