STOCKHOLDERS' EQUITY: (Details Textual) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Share-Based Compensation Arrangement By Share-Based Payment Award Options Vested In Period	108,725	79,292	108,725	656,079
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Stock Options	$ 51,000		$ 51,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition			11 months
Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value (in dollars per share)			$ 3.23
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Share-based Awards Other than Options	280,000		280,000
Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition			14 months
Stock-based compensation	47,000	46,000	90,000	90,000
Repurchase Of Common Stock Value			68,000
Repurchase Program 2013 [Member]
Stock Repurchase Program, Authorized Amount			3,500,000
May 2013 Repurchase Program [Member]
Stock Repurchase Program, Authorized Amount			1,500,000
January Repurchase Program 2013 [Member]
Stock Repurchase Program, Authorized Amount			2,000,000
Non Executive Directors [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total	109,645		109,645
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			50.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			2 years
Non Executive Directors One [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total			21,929
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures, Total			50,000
Non Executive Directors Two [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total			21,929
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures, Total			50,000
Non Executive Directors Three [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total			21,929
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures, Total			50,000
Non Executive Directors Four [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total			21,929
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures, Total			50,000
Non Executive Directors Five [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total			21,929
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures, Total			50,000
Common Class A [Member]
Repurchase Of Common Stock Shares	24,419		31,569
Repurchase Of Common Stock Price Per Share (in dollars per share)	$ 2.35		$ 2.16
Stock Repurchase Program, Remaining Authorized Repurchase Amount			1,300,000
Repurchase Of Common Stock Value	57,000		68,000
Common Class A [Member] | Stock Option and Restricted Stock Grant Plan 1999 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	1,408,099		1,408,099
Common Class D [Member]
Repurchase Of Common Stock Shares	1,166,300		2,118,274
Repurchase Of Common Stock Price Per Share (in dollars per share)	$ 2.29		$ 1.98
Stock Repurchase Program, Remaining Authorized Repurchase Amount			1,300,000
Repurchase Of Common Stock Value	$ 2,674,000		$ 4,189,000
Common Class D [Member] | Stock Option and Restricted Stock Grant Plan 1999 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	10,816,198		10,816,198
Common Class D [Member] | Stock Plan 2009 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	8,250,000		8,250,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	4,614,627		4,614,627