CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Current Assets | ||
| Accounts receivable, allowance for doubtful accounts | $ 1,781 | $ 1,747 |
| Stockholders' Equity: | ||
| Preferred stock, par value (in dollars per share) | $ 0 | $ 0 |
| Preferred stock, authorized (in shares) | 1,000,000 | 1,000,000 |
| Preferred stock, issued (in shares) | 0 | 0 |
| Class A [Member] | ||
| Stockholders' Equity: | ||
| Common stock, par value (in dollars per share) | $ 0.10 | $ 0.10 |
| Common stock, authorized (in shares) | 10,000,000 | 10,000,000 |
| Common stock, outstanding (in shares) | 2,174,912 | 2,174,912 |
| Common stock, treasury shares (in shares) | 1,072,769 | 1,072,769 |
| Class B [Member] | ||
| Stockholders' Equity: | ||
| Common stock, par value (in dollars per share) | $ 0.10 | $ 0.10 |
| Common stock, authorized (in shares) | 30,000,000 | 30,000,000 |
| Common stock, outstanding (in shares) | 9,851,652 | 9,701,977 |
| Common stock, treasury shares (in shares) | 3,218,307 | 3,218,307 |