Commitments and Contingencies - Joint-Owned Utility Poles (Details) - Jointly owned utility plant	3 Months Ended
Mar. 31, 2017 item
Loss Contingencies [Line Items]
Number of counties	3
Number of joint pole owners	1
Maximum
Loss Contingencies [Line Items]
Number of counties	4
Dispute resolution process
Loss Contingencies [Line Items]
Number of utilities	1

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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