Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net income	$ 1,103,000	$ 1,019,000	$ 2,457,000	$ 2,323,000
Other comprehensive income (loss):
Change in unrealized gain (loss) on marketable securities, net of tax	(208,000)	28,000	(243,000)	(50,000)
Comprehensive income	$ 895,000	$ 1,047,000	$ 2,214,000	$ 2,273,000