Commitments 3 (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Water Purchase Commitments [Member] \| GSWC
Purchase commitments
Total commitment under agreement	$ 4,794
Bear Valley Electric \| Electric Service Utility Operations [Member]
Purchase commitments
Total commitment under agreement	$ 9,600

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.

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