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Asset Sales - Narrative (Details) $ in Millions | 3 Months Ended
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Jun. 30, 2019 USD ($)
DIG's High-Voltage Equipment to ITC | Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |
Gain on disposition of assets | $ 16

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- Details
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