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Regulatory Assets and Liabilities (Narrative) (Details) $ in Millions, $ in Millions |  |  |  | 1 Months Ended | 6 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 01, 2019 USD ($) | Sep. 12, 2018 USD ($) | Aug. 20, 2018 USD ($) | Jan. 31, 2020 USD ($) | Sep. 30, 2019 USD ($) | Dec. 31, 2018 CAD ($) | Jun. 30, 2018 | Jun. 30, 2018 | Dec. 31, 2021 CAD ($) | Dec. 31, 2020 CAD ($) | Dec. 31, 2019 CAD ($) km MW | Dec. 31, 2019 USD ($) MW | Dec. 31, 2018 CAD ($) | Dec. 31, 2019 USD ($) km | Dec. 31, 2018 USD ($) | Dec. 13, 2016 CAD ($) | Dec. 31, 2015 CAD ($)
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Liabilities |  |  |  |  |  | $ 2,610 |  |  |  |  | $ 2,181 |  | $ 2,610 |  |  |  |
Depreciation and amortization |  |  |  |  |  |  |  |  |  |  | 903 |  | 916 |  |  |  |
Utilities Operating Expense, Maintenance, Operations, and Other Costs and Expenses |  |  |  |  |  |  |  |  |  |  | 1,464 |  | 1,580 |  |  |  |
Contractual Obligation, to be Paid, Year One |  |  |  |  |  |  |  |  |  |  | 1,950 |  |  |  |  |  |
Contractual Obligation, to be Paid, Year Two |  |  |  |  |  |  |  |  |  |  | 970 |  |  |  |  |  |
Income tax expense (recovery) |  |  |  |  |  |  |  |  |  |  | (61) |  | (69) |  |  |  |
Regulatory Assets |  |  |  |  |  | 1,569 |  |  |  |  | $ 1,552 |  | $ 1,569 |  |  |  |
State income tax |  |  |  |  |  |  |  |  |  |  | 8.00% | 8.00% | 8.00% |  |  |  |
Regulated fuel adjustment mechanism |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Liabilities |  |  |  |  |  | 161 |  |  |  |  | $ 115 |  | $ 161 |  |  |  |
Cost recovery clauses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Assets |  |  |  |  |  | 75 |  |  |  |  | 13 |  | 75 |  |  |  |
Renewable Energy Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Assets |  |  |  |  |  | 24 |  |  |  |  | 19 |  | 24 |  |  |  |
Environmental remediations |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Assets |  |  |  |  |  | 31 |  |  |  |  | 26 |  | 31 |  |  |  |
Unamortized defeasance costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Assets |  |  |  |  |  | $ 26 |  |  |  |  | 19 |  | $ 26 |  |  |  |
Emera Maine |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contractual Obligation, to be Paid, Year One |  |  |  |  |  |  |  |  |  |  | 49 |  |  |  |  |  |
Contractual Obligation, to be Paid, Year Two |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  |  |  |  |
Barbados Light and Power Company Limited |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 10.00% | 10.00% |  |  |  |  |
Deferred Tax Liabilities, Regulatory Assets and Liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 6.9 |  |  |
Income tax expense (recovery) |  |  |  |  |  |  |  |  |  |  |  | $ 9.6 |  |  |  |  |
GBPC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  | 8.44% |  |  |  |  | 8.50% | 8.50% | 8.50% |  |  |  |
GBPC | Loss from Catastrophes | Hurricane |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Storm cost |  |  |  |  |  |  |  |  |  |  | $ 15 | $ 12.0 |  |  |  |  |
Storm Reserve |  |  |  |  |  |  |  |  |  |  | $ 23 |  |  |  |  |  |
Brunswick Pipeline |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Length Of Pipeline | km |  |  |  |  |  |  |  |  |  |  | 145 |  |  | 145 |  |  |
Public Utilities, Property, Plant and Equipment, Transmission and Distribution, Useful Life |  |  |  |  |  |  |  |  |  |  | 25 years | 25 years |  |  |  |  |
NSPI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulated common equity component |  |  |  |  |  |  |  |  |  |  | 40.00% | 40.00% |  |  |  |  |
Contractual Obligation, to be Paid, Year One |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  |  |  |  |
Contractual Obligation, to be Paid, Year Two |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |
NSPI | NSPML |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Phase-in Plan, Amount of Costs Deferred for Rate-making Purposes |  |  |  |  |  |  |  |  |  |  | 10 |  |  |  |  |  |
Regulatory Liabilities |  |  |  |  |  | $ 110 |  |  |  |  | 111 |  | $ 110 |  |  |  |
Approved payment in period |  |  |  |  |  |  |  |  |  |  | $ 101 |  |  |  |  |  |
Interim cost assessment, holdback |  |  |  |  |  |  |  |  |  |  | The payments are subject to a holdback of $10 million pending UARB agreement that a minimum of $10 million in benefits from the Maritime Link are realized for NSPI customers. If the $10 million in benefits is realized, the UARB will direct NSPI to pay the $10 million to NSPML for that year. If not realized, then the UARB will direct NSPI to pay to NSPML only that portion that is realized and the balance will be refunded to customers through NSPI’s FAM. | The payments are subject to a holdback of $10 million pending UARB agreement that a minimum of $10 million in benefits from the Maritime Link are realized for NSPI customers. If the $10 million in benefits is realized, the UARB will direct NSPI to pay the $10 million to NSPML for that year. If not realized, then the UARB will direct NSPI to pay to NSPML only that portion that is realized and the balance will be refunded to customers through NSPI’s FAM. |  |  |  |  |
Holdback payable |  |  |  |  |  |  |  |  |  |  | $ 6 |  |  |  |  |  |
Depreciation and amortization |  |  |  |  |  |  |  |  |  |  | 53 |  | 53 |  |  |  |
Utilities Operating Expense, Maintenance, Operations, and Other Costs and Expenses |  |  |  |  |  |  |  |  |  |  | 115 |  |  |  |  |  |
Depreciation and amortization of financing costs |  |  |  |  |  |  |  |  |  |  | 30 |  |  |  |  |  |
Contractual Obligation, to be Paid, Year One |  |  |  |  |  |  |  |  |  |  | 145 |  |  |  |  |  |
Contractual Obligation, to be Paid, Year Two |  |  |  |  |  |  |  |  |  |  | 111 |  |  |  |  |  |
Phase-in Plan, Amount of Capitalized Costs Recovered |  |  |  |  |  |  |  |  |  |  | $ 35 |  | 17 |  |  |  |
Regulatory Asset Recovery Assessments |  |  |  |  |  |  |  |  |  |  | On December 6, 2019, the UARB approved NSPI’s three-year fuel stability plan which results in an average annual overall rate increase of 1.5 per cent to recover fuel costs for the period of 2020 through 2022. For the years 2020 to 2022, differences between actual fuel costs and fuel revenues recovered from customers will be recovered from or returned to customers after 2022. The decision further directed that annual excess non-fuel revenues above NSPI’s approved range of ROE are to be applied to the FAM. | On December 6, 2019, the UARB approved NSPI’s three-year fuel stability plan which results in an average annual overall rate increase of 1.5 per cent to recover fuel costs for the period of 2020 through 2022. For the years 2020 to 2022, differences between actual fuel costs and fuel revenues recovered from customers will be recovered from or returned to customers after 2022. The decision further directed that annual excess non-fuel revenues above NSPI’s approved range of ROE are to be applied to the FAM. |  |  |  |  |
Recovery Period |  |  |  |  |  |  |  |  |  |  | 3 years | 3 years |  |  |  |  |
NSPI | NSPML | Regulated fuel adjustment mechanism |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Holdback payable |  |  |  |  |  |  |  |  |  |  | $ 10 |  |  |  |  |  |
NSPI | NSPML | Regulated fuel adjustment mechanism | Scenario Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Phase-in Plan, Amount of Costs Deferred for Rate-making Purposes |  |  |  |  |  |  |  |  |  |  | $ 52 |  |  |  |  |  |
Phase-in Plan, Amount of Capitalized Costs Recovered |  |  |  |  |  |  |  |  | $ 12 | $ 40 |  |  |  |  |  |  |
Regulatory Asset Recovery Assessments |  |  |  |  |  |  |  |  |  |  | The UARB’s decision to approve NSPI’s 2020 through 2022 Fuel Stability Plan outlined the treatment of the reduced 2019 NSPML assessment of $52 million plus interest. The reduced assessment will be refunded to most customers through a reduction incorporated into their 2020 through 2022 rates and the remaining customers will receive a one-time on bill credit in 2020.The credit to customers will be approximately $40 million plus interest in 2020, with the remaining $12 million plus interest to be returned to customers subsequent to 2022. | The UARB’s decision to approve NSPI’s 2020 through 2022 Fuel Stability Plan outlined the treatment of the reduced 2019 NSPML assessment of $52 million plus interest. The reduced assessment will be refunded to most customers through a reduction incorporated into their 2020 through 2022 rates and the remaining customers will receive a one-time on bill credit in 2020.The credit to customers will be approximately $40 million plus interest in 2020, with the remaining $12 million plus interest to be returned to customers subsequent to 2022. |  |  |  |  |
NSPI | Renewable Energy Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Replacement program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 31 | $ 35
NSPI | Unamortized defeasance costs | Defeased debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  | 759 |  |  |  |  | $ 740 |  | 759 |  |  |  |
NMGC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, Disclosure of Rate Matters |  |  |  |  |  |  |  |  |  |  | NMGC is subject to regulation by the NMPRC. The NMPRC sets rates at a level that allows NMGC to collect total revenues equal to its cost of providing service, plus an appropriate return on invested capital. | NMGC is subject to regulation by the NMPRC. The NMPRC sets rates at a level that allows NMGC to collect total revenues equal to its cost of providing service, plus an appropriate return on invested capital. |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 9.10% | 9.10% |  |  |  |  |
Allowed equity capital structure |  |  |  |  |  |  |  |  |  |  | 52.00% | 52.00% |  |  |  |  |
Contractual Obligation, to be Paid, Year One |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  |  |  |  |
Contractual Obligation, to be Paid, Year Two |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  |  |  |  |
Deferred Tax Liabilities, Regulatory Assets and Liabilities |  |  |  |  |  | $ 11 |  |  |  |  |  |  | $ 11 |  | $ 8.0 |  |
PGS |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, Disclosure of Rate Matters |  |  |  |  |  |  |  |  |  |  | PGS is regulated by the FPSC. The FPSC sets rates at a level that allows utilities such as PGS to collect total revenues or revenue requirements equal to their cost of providing service, plus an appropriate return on invested capital. | PGS is regulated by the FPSC. The FPSC sets rates at a level that allows utilities such as PGS to collect total revenues or revenue requirements equal to their cost of providing service, plus an appropriate return on invested capital. |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 10.75% | 10.75% |  |  |  |  |
Allowed equity capital structure |  |  |  |  |  |  |  |  |  |  | 54.70% | 54.70% |  |  |  |  |
Length Of Pipeline | km |  |  |  |  |  |  |  |  |  |  | 800 |  |  | 800 |  |  |
Contractual Obligation, to be Paid, Year One |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  |  |  |  |
Contractual Obligation, to be Paid, Year Two |  |  |  |  |  |  |  |  |  |  | $ 61 |  |  |  |  |  |
Length Of Pipeline, percentage |  |  |  |  |  |  |  |  |  |  | 5.00% |  |  | 5.00% |  |  |
Replacement program |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 80.0 |  |  |
Amortization of Regulatory Asset |  | $ 11.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public utilities base rate decrease | $ 12.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reduction in annual depreciation | $ 10.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Asset Amortization Period |  |  |  |  |  |  |  |  |  |  | 10 years | 10 years |  |  |  |  |
Tampa Electric |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contractual Obligation, to be Paid, Year One |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  |  |  |  |
Contractual Obligation, to be Paid, Year Two |  |  |  |  |  |  |  |  |  |  | $ 301 |  |  |  |  |  |
State income tax |  |  |  |  |  |  |  |  |  |  | 4.46% | 4.46% | 5.50% |  |  |  |
Tampa Electric | Hurricane |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Storm cost |  |  |  |  | $ 8.0 |  |  |  |  |  |  |  |  |  |  |  |
Tampa Electric | SoBRA |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, Property, Plant and Equipment, Generation or Processing |  |  |  |  |  |  |  |  |  |  |  |  |  | 820.0 |  |  |
Estimated revenue in MW | MW |  |  |  |  |  |  |  |  |  |  | 600 | 600 |  |  |  |  |
Tampa Electric | SoBRA | Scenario Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, Property, Plant and Equipment, Generation or Processing |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 30.0 |  |  |
Maritime Link Project | NSPI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contractual Obligation, to be Paid, Year One |  |  |  |  |  |  |  |  |  |  | $ 145 |  |  |  |  |  |
Contractual Obligation, to be Paid, Year Two |  |  |  |  |  |  |  |  |  |  | $ 164 |  |  |  |  |  |
Steam turbine | GBPC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, Property, Plant and Equipment, Amount of Loss (Recovery) on Plant Abandonment |  |  |  |  |  |  |  |  |  |  |  | $ 21.0 |  |  |  |  |
New Mexico Public Regulatory | NMGC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Phase-in Plan, Amount of Capitalized Costs Recovered |  |  |  |  |  |  |  |  |  |  |  | $ 3.0 |  |  |  |  |
Public Utilities, Disclosure of Regulatory Matters Pending |  |  |  |  |  |  |  |  |  |  | On December 23, 2019, NMGC filed a future year rate case on December 23, 2019 for new rates effective January 2021. The proposed new rates reflect the recovery of capital investment in pipelines and related infrastructure. The estimated annual incremental revenue requirement is approximately $13 million USD. A decision from the NMPRC is expected in late 2020. | On December 23, 2019, NMGC filed a future year rate case on December 23, 2019 for new rates effective January 2021. The proposed new rates reflect the recovery of capital investment in pipelines and related infrastructure. The estimated annual incremental revenue requirement is approximately $13 million USD. A decision from the NMPRC is expected in late 2020. |  |  |  |  |
Public Utilities, Phase-in Plan Terms |  |  |  |  |  |  |  |  |  |  | The new rates are being phased in over two years and are expected to result in an annual revenue increase of approximately $3 million USD. | The new rates are being phased in over two years and are expected to result in an annual revenue increase of approximately $3 million USD. |  |  |  |  |
Public Utilities, Requested Rate Increase (Decrease), Amount |  |  |  |  |  |  |  |  |  |  |  | $ 13.0 |  |  |  |  |
Income tax expense (recovery) |  |  |  |  |  |  |  |  |  |  | $ 7 | $ 5.0 |  |  |  |  |
MPUC | Emera Maine |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved average annual increase |  |  |  |  |  |  | 5.30% |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  | 9.00% |  |  | 9.35% | 9.35% |  |  |  |  |
Allowed equity capital structure |  |  |  |  |  |  |  |  |  |  | 49.00% | 49.00% | 49.00% |  |  |  |
FERC | Emera Maine |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 10.57% | 10.57% | 10.57% |  |  |  |
FERC | Electric Transmission | Emera Maine |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 9.60% | 9.60% | 9.60% |  |  |  |
Electricity Plan Act | NSPI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved average annual increase |  |  |  |  |  |  |  |  |  |  | 1.50% | 1.50% |  |  |  |  |
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage |  |  |  |  |  |  |  |  |  |  | 1.50% | 1.50% |  |  |  |  |
Florida Public Service Commission | Tampa Electric |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, Disclosure of Rate Matters |  |  |  |  |  |  |  |  |  |  | Tampa Electric is regulated by the FPSC. Tampa Electric is also subject to regulation by the Federal Energy Regulatory Commission (“FERC”). The FPSC sets rates at a level that allows utilities such as Tampa Electric to collect total revenues or revenue requirements equal to their cost of providing service, plus an appropriate return on invested capital. | Tampa Electric is regulated by the FPSC. Tampa Electric is also subject to regulation by the Federal Energy Regulatory Commission (“FERC”). The FPSC sets rates at a level that allows utilities such as Tampa Electric to collect total revenues or revenue requirements equal to their cost of providing service, plus an appropriate return on invested capital. |  |  |  |  |
Allowed equity capital structure |  |  |  |  |  |  |  |  |  |  | 54.00% | 54.00% |  |  |  |  |
Public Utilities, Approved Rate Increase (Decrease), Amount |  |  | $ 103.0 |  |  |  |  |  |  |  |  | $ 5.0 |  |  |  |  |
Florida Public Service Commission | Tampa Electric | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Storm cost |  |  |  | $ 12.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Florida Public Service Commission | Tampa Electric | Cost recovery clauses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 10.25% | 10.25% |  |  |  |  |
Florida Public Service Commission | Tampa Electric | SoBRA |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated revenue |  |  |  |  |  |  |  |  |  |  |  | $ 96.0 |  |  |  |  |
Estimated revenue in MW | MW |  |  |  |  |  |  |  |  |  |  | 554 | 554 |  |  |  |  |
Range, Minimum | NSPI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 8.75% | 8.75% |  |  |  |  |
Range, Minimum | NSPI | NSPML |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 8.75% | 8.75% |  |  |  |  |
Range, Minimum | PGS |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 9.25% | 9.25% |  |  |  |  |
Range, Minimum | FERC | ISO-New England ("ISO-NE") Open Access Transmission Tariff ("OATT") | Emera Maine |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 11.07% | 11.07% | 11.07% |  |  |  |
Range, Minimum | Florida Public Service Commission | Tampa Electric |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 9.25% | 9.25% | 9.25% |  |  |  |
Range, Maximum | NSPI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 9.25% | 9.25% |  |  |  |  |
Range, Maximum | NSPI | NSPML |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 9.25% | 9.25% |  |  |  |  |
Regulated common equity component |  |  |  |  |  |  |  |  |  |  | 30.00% | 30.00% |  |  |  |  |
Range, Maximum | PGS |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 11.75% | 11.75% |  |  |  |  |
Range, Maximum | FERC | ISO-New England ("ISO-NE") Open Access Transmission Tariff ("OATT") | Emera Maine |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 11.74% | 11.74% | 11.74% |  |  |  |
Range, Maximum | Florida Public Service Commission | Tampa Electric |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Approved regulated return on equity |  |  |  |  |  |  |  |  |  |  | 11.25% | 11.25% | 11.25% |  |  |  |

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