Note 13 - Significant Customers	12 Months Ended
Dec. 31, 2017
Notes
Note 13 - Significant Customers	Note 13 - Significant Customers As of December 31, 2017, Customers A and B each represented 10% of accounts receivable, and Customer F represented 30% of costs and estimated earnings in excess of billings. As of December 31, 2016, Customers C and D represented 19% and 29% of accounts receivable, respectively, and Customers E and A represented 48% and 18% of costs and estimated earnings in excess of billings, respectively. For the year ended December 31, 2017, Customer F represented 11% of total sales. For the year ended December 31, 2016, Customer E represented 23% of total sales.

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

Name:	us-gaap_ConcentrationRiskDisclosureTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration