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Schedule II - Valuation and Qualifying Accounts (Tables) | 12 Months Ended
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Dec. 31, 2018
Notes Tables |
Summary of Valuation and Qualifying Accounts [Table Text Block] |
|  | Balance at Beginning of Period |  |  | Charged to Profit and Loss |  |  | Deduction from Reserves |  |  | Balance at End of Period |
Year Ended December 31, 2018: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Allowance for doubtful accounts |  | $ | 477 |  |  | $ | 449 |  |  | $ | (266 | ) |  | $ | 660 |
Valuation allowance for deferred income tax assets |  |  | 10,413 |  |  |  | 1,785 |  |  |  | (2,765 | ) |  |  | 9,433 |
Year Ended December 31, 2017: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Allowance for doubtful accounts |  | $ | 515 |  |  | $ | 637 |  |  | $ | (675 | ) |  | $ | 477 |
Valuation allowance for deferred income tax assets |  |  | 8,217 |  |  |  | 2,196 |  |  |  | - |  |  |  | 10,413 |
Year Ended December 31, 2016: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Allowance for doubtful accounts |  | $ | 751 | (1) |  | $ | 295 |  |  | $ | (531 | ) |  | $ | 515 |
Valuation allowance for deferred income tax assets |  |  | 7,057 |  |  |  | 1,160 |  |  |  | - |  |  |  | 8,217 |

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- Definition A schedule of allowance and reserve accounts including their beginning and ending balances, as well as a reconciliation by type of activity during the period. Alternatively, disclosure of the required information may be within the footnotes to the financial statements or a supplemental schedule to the financial statements. + References No definition available. + Details
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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | na
Period Type: | duration