Note 11 - Contract Assets and Contract Liabilities (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Contract with Customer, Asset, Net, Current, Total	$ 1,967,000	$ 962,000
Increase (Decrease) in Contract with Customer, Asset	1,005,000	217,000
Contract with Customer, Liability, Current	$ 1,004,000	$ 406,000

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

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Amount of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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