Segment Information - Financial Data by Segment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Sales to external customers	$ 22,837us-gaap_SalesRevenueGoodsNet	$ 19,152us-gaap_SalesRevenueGoodsNet
Operating income	827us-gaap_OperatingIncomeLoss	625us-gaap_OperatingIncomeLoss
Interest expense, net	130us-gaap_InterestIncomeExpenseNet	83us-gaap_InterestIncomeExpenseNet
Other expense, net	76us-gaap_OtherNonoperatingIncomeExpense	19us-gaap_OtherNonoperatingIncomeExpense
Consolidated income before income taxes	621	523
Assets	78,800us-gaap_Assets		79,308us-gaap_Assets
United States
Sales to external customers	20,134	16,103
Operating income	971	676
Assets	70,917		70,526
Canada
Sales to external customers	1,244	1,511
Operating income	(108)	32
Assets	4,090		4,363
Europe
Sales to external customers	1,459	1,538
Operating income	(36)	(83)
Assets	$ 3,793		$ 4,419

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The net amount of operating interest income (expense).

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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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