Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Interest paid	$ 1,285	$ 1,360
Income taxes paid	754	750
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in equity	76	76
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in equity	5	5
Common Stock \| Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued	5
Additional Paid-in Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in equity	71	$ 71
Additional Paid-in Capital \| Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in equity	$ 71

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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Amount of cash paid for interest. Includes, but is not limited to, payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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The fair value of stock issued in noncash financing activities.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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