CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Property and equipment, accumulated depreciation	$ 6,689,000	$ 6,462,000
Common stock, par value (dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	25,000,000	25,000,000
Common stock, shares issued	10,340,629	10,182,583
Common stock, shares outstanding	8,975,865	8,904,902
Treasury stock, shares	1,364,764	1,277,681
Long-term Investments Carried at Fair Value	$ 250

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Face amount or stated value per share of common stock.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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Long-term Investments Carried at Fair Value

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