Cash Equivalents, Qualification, Maximum Original Maturity of Short-term Investments

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Customer Deposits, Deposit Requirements, Large Custom Contracts, Maximum Percentage

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A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The current portion of the amount recognized for uncertain tax positions as of the balance sheet date.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Summary of Significant Accounting Policies (Narrative) (Details)	3 Months Ended								12 Months Ended
	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) segment	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Revenue from External Customer [Line Items]
Cash equivalents, qualification, maximum original maturity of short-term investments									3 months
Customer deposit requirements, large custom contracts, maximum percentage									50.00%
Allowance for doubtful accounts	$ 833,000				$ 507,000				$ 833,000	$ 507,000
Total revenue	25,755,000	$ 21,193,000	$ 24,230,000	$ 24,741,000	27,101,000	$ 25,599,000	$ 21,952,000	$ 22,322,000	95,919,000	96,974,000	$ 89,248,000
Impairment of goodwill									0	0
Product warranty reserves	103,000				0				103,000	0
Uncertain tax positions	$ 0				$ 0				$ 0	$ 0
Number of business segments \| segment									1
Bill and Hold Arrangement
Revenue from External Customer [Line Items]
Total revenue									$ 4,000,000