STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($)	Common Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings (Accumulated Deficit) [Member]	Total
Balances at Dec. 31, 2017	$ 119,000	$ 15,361,000	$ (639,000)	$ 14,841,000
Balances, shares at Dec. 31, 2017	11,914,000
Issuance of common stock, net	$ 0	49,000		49,000
Issuance of common stock, net, shares	49,000
Value of stock-based compensation		67,000		67,000
Net income (loss)			164,000	164,000
Balances at Mar. 31, 2018	$ 119,000	15,477,000	(475,000)	15,121,000
Balances, shares at Mar. 31, 2018	11,963,000
Balances at Dec. 31, 2017	$ 119,000	15,361,000	(639,000)	14,841,000
Balances, shares at Dec. 31, 2017	11,914,000
Net income (loss)				993,000
Balances at Sep. 30, 2018	$ 118,000	15,345,000	354,000	15,817,000
Balances, shares at Sep. 30, 2018	11,848,000
Balances at Mar. 31, 2018	$ 119,000	15,477,000	(475,000)	15,121,000
Balances, shares at Mar. 31, 2018	11,963,000
Value of stock-based compensation		82,000		82,000
Repurchase of common stock upon vesting of restricted stock awards and vesting of restricted stock units		(14,000)		(14,000)
Repurchase of common stock upon vesting of restricted stock awards and vesting of restricted stock units, shares	(9,000)
Repurchase of common stock, net		(187,000)		(187,000)
Repurchase of common stock, net, shares	(103,000)
Net income (loss)			184,000	184,000
Balances at Jun. 30, 2018	$ 119,000	15,358,000	(291,000)	15,186,000
Balances, shares at Jun. 30, 2018	11,851,000
Value of stock-based compensation		128,000		128,000
Repurchase of common stock upon vesting of restricted stock awards and vesting of restricted stock units		(60,000)		(60,000)
Repurchase of common stock upon vesting of restricted stock awards and vesting of restricted stock units, shares	42,000
Repurchase of common stock, net	$ (1,000)	(81,000)		(82,000)
Repurchase of common stock, net, shares	(45,000)
Net income (loss)			645,000	645,000
Balances at Sep. 30, 2018	$ 118,000	15,345,000	354,000	15,817,000
Balances, shares at Sep. 30, 2018	11,848,000
Balances at Dec. 31, 2018	$ 118,000	15,442,000	760,000	16,320,000
Balances, shares at Dec. 31, 2018	11,840,000
Issuance of common stock, net	$ 1,000	107,000		108,000
Issuance of common stock, net, shares	107,000
Value of stock-based compensation		138,000		138,000
Net income (loss)			(1,096,000)	(1,096,000)
Balances at Mar. 31, 2019	$ 119,000	15,687,000	(336,000)	15,470,000
Balances, shares at Mar. 31, 2019	11,947,000
Balances at Dec. 31, 2018	$ 118,000	15,442,000	760,000	16,320,000
Balances, shares at Dec. 31, 2018	11,840,000
Net income (loss)				(2,562,000)
Balances at Sep. 30, 2019	$ 121,000	15,890,000	(1,802,000)	14,209,000
Balances, shares at Sep. 30, 2019	12,074,000
Balances at Mar. 31, 2019	$ 119,000	15,687,000	(336,000)	15,470,000
Balances, shares at Mar. 31, 2019	11,947,000
Value of stock-based compensation		139,000		139,000
Repurchase of common stock upon vesting of restricted stock awards and vesting of restricted stock units	$ 1,000	(10,000)		(9,000)
Repurchase of common stock upon vesting of restricted stock awards and vesting of restricted stock units, shares	98,000
Net income (loss)			(488,000)	(488,000)
Balances at Jun. 30, 2019	$ 120,000	15,816,000	(824,000)	15,112,000
Balances, shares at Jun. 30, 2019	12,045,000
Value of stock-based compensation		101,000		101,000
Repurchase of common stock upon vesting of restricted stock awards and vesting of restricted stock units	$ 1,000	(27,000)		(26,000)
Repurchase of common stock upon vesting of restricted stock awards and vesting of restricted stock units, shares	29,000
Net income (loss)			(978,000)	(978,000)
Balances at Sep. 30, 2019	$ 121,000	$ 15,890,000	$ (1,802,000)	$ 14,209,000
Balances, shares at Sep. 30, 2019	12,074,000