Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Net loss	$ (7,709)	$ (5,258)
Other comprehensive (loss) income:
Actuarial loss (gain)	268	174
Amortization of actuarial loss	(108)	(87)
Adjustments to net periodic postretirement loss (benefit)	160	87
Comprehensive loss	$ (7,869)	$ (5,345)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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