Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
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Note 11 - Segment and Enterprise-wide Disclosures - Net Sales to Unaffiliated Customers by Geography (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Total net sales	$ 28,389	$ 24,165	$ 27,020	$ 25,994	$ 26,153	$ 24,822	$ 25,753	$ 24,139	$ 105,568	$ 100,867	$ 89,151
UNITED STATES
Total net sales									59,078	58,470	50,439
GERMANY
Total net sales									12,445	11,576	10,350
Other Countries [Member]
Total net sales									$ 34,045	$ 30,821	$ 28,362