SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS (Details) - Allowance for doubtful accounts and sales allowances [Member] - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Valuation Allowances and Reserves [Roll Forward] | |||
| Allowance for doubtful accounts and sales allowances, Balance at Beginning of Year | $ 3,588 | $ 4,164 | $ 4,453 |
| Allowance for doubtful accounts and sales allowances, Charged to Costs and Expenses | 573 | 1,419 | 961 |
| Allowance for doubtful accounts and sales allowances, Charged to Other Accounts | 0 | 19 | 0 |
| Allowance for doubtful accounts and sales allowances, Uncollectible accounts written off, net of recoveries | (1,498) | (2,014) | (1,250) |
| Allowance for doubtful accounts and sales allowances, Balance at End of Year | $ 2,663 | $ 3,588 | $ 4,164 |