CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2016	Dec. 31, 2015
Preferred Stock, par value per share	$ 5.00	$ 5.00
Preferred Stock, shares authorized	2,000,000	2,000,000
Preferred Stock, shares issued	0	0
Treasury stock, shares	8,443,902	8,455,293
Common Class A [Member]
Common Stock, par value per share	$ 0.001	$ 0.001
Common Stock, shares authorized	100,000,000	100,000,000
Common Stock, shares issued	37,315,016	37,238,913
Common Class B [Member]
Common Stock, par value per share	$ 0.001	$ 0.001
Common Stock, shares authorized	25,000,000	25,000,000
Common Stock, shares issued	3,235,048	3,235,048
Common Stock, shares outstanding	3,235,048	3,235,048