Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands |
Sep. 30, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Statement of Financial Position [Abstract] | ||
| Accounts receivable, less allowances | $ 3,149 | $ 2,326 |
| Common stock, par value | $ 2 | $ 2 |
| Common stock, shares authorized | 15,000,000 | 15,000,000 |
| Common stock, shares issued | 5,125,849 | 5,221,062 |
| Common stock, shares outstanding | 5,125,849 | 5,221,062 |
| Common stock, shares issued to rabbi trust | 297,281 | 296,635 |
| Treasury stock shares | 1,122,290 | 1,018,013 |