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Termination of Proposed Acquisition by Hydro One - Additional Information (Details) - USD ($) $ in Thousands |  | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jan. 24, 2019 | Sep. 30, 2019 | Dec. 31, 2019
Business Acquisition [Line Items] |  |  |
Merger termination fee |  | $ 103,000 |
Merger transaction costs |  | $ 19,675 | $ 19,700
Hydro One [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Merger termination fee | $ 103,000 |  |

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- Definition Termination Fee Received from Canceled Business Acquisition + References No definition available. + Details
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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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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460 + Details
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- Details
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