2. Revenue: Schedule of contract balances (Details) - USD ($) $ in Thousands	Jun. 29, 2018	Dec. 31, 2017
Details
Accounts receivable, net	$ 5,504	$ 3,794
Contract revenue in excess of billings	4,657
Other Liabilities, Current	$ 9,229

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

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