Related Party Transactions (Details) - ValleyNet - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
(in thousands)
Facility lease revenue	$ 1,677	$ 2,201	$ 2,384
Cost of goods and services	3,362	3,673	$ 3,067
(in thousands)
Account receivable related to ValleyNet	253	180
Accounts payable related to ValleyNet	$ 173	$ 303

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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Direct costs arising from transactions with related parties who are not affiliates or joint Ventures. These costs are categorized as cost of goods sold.

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