Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Allowance for accounts receivable	$ 671	$ 759
Accumulated amortization on other intangibles, deferred costs and investments	$ 14,711	$ 13,682
Preferred Stock, Shares Authorized	1,500	1,500
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Treasury stock, shares (in shares)	1,735	1,703
Class A Common Stock
Common Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, Shares Authorized	35,000	35,000
Common Stock, Shares, Issued	6,771	6,732
Class B Common Stock
Common Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, Shares Authorized	3,500	3,500
Common Stock, Shares, Issued	954	923
Common Stock, Shares, Outstanding	954	923