Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|
Allowance for doubtful accounts receivable | |||
Deducted from asset accounts: | |||
Balance at Beginning of Period | $ 857 | $ 1,197 | $ 1,578 |
Charged to Costs and Expenses | 84 | (34) | 692 |
Charged to Other Accounts | 0 | 0 | 0 |
Deduction | 301 | 306 | 1,073 |
Balance at End of Period | 640 | 857 | 1,197 |
Inventory reserves and obsolescence | |||
Deducted from asset accounts: | |||
Balance at Beginning of Period | 14,407 | 7,869 | 8,193 |
Charged to Costs and Expenses | 3,521 | 10,564 | 3,842 |
Charged to Other Accounts | 0 | 0 | 0 |
Deduction | 4,752 | 4,026 | 4,166 |
Balance at End of Period | $ 13,176 | $ 14,407 | $ 7,869 |