Consolidated Balance Sheets (Parenthetical) $ in Thousands	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares
Accounts receivable, net of allowances of $19,801 in 2015 and $17,327 in 2014 | $	$ 19,801	$ 17,327
Shares Outstanding Class A
Common stock, par value | $ / shares	$ 1	$ 1
Common stock, shares outstanding | shares	5,265,446	5,662,214
Shares Outstanding Class B
Common stock, par value | $ / shares	$ 1	$ 1
Common stock, shares outstanding | shares	1,571,727	1,573,292
Common stock, convertible conversion ratio	1	1