Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Current Assets:
Accounts receivable, allowances	$ 38	$ 35
Stockholders’ Equity
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	10,000,000	10,000,000
Common stock, shares issued (in shares)	4,779,977	4,774,477
Common stock, shares outstanding (in shares)	4,698,393	4,692,893
Treasury stock, (in shares)	81,584	81,584