FERC (Details 7) $ in Millions	May 30, 2019 USD ($)
Tax Cuts and Jobs Act [Member] \| Natural gas rate proceeding [Member] \| FERC [Member]
Public Utilities, General Disclosures [Line Items]
Public utilities, interim rate increase (decrease), amount	$ 4.5

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.

No definition available.

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