Accrued Liabilities and Other Current Liabilities - Valve installation (Details) - Intrastate Pipeline Company $ in Millions	1 Months Ended
Apr. 30, 2018 USD ($)
Other Commitments [Line Items]
Period after valve installation for reimbursement of costs	30 days
Percentage of valve costs for reimbursement	50.00%
Maximum reimbursement payment per agreement	$ 2.0

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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