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Schedule II Valuation of Qualifying Accounts and Reserves | 12 Months Ended
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Dec. 31, 2018
Schedule II Valuation and Qualifying Accounts and Reserves [Abstract] |
SEC Schedule, 12-09, Schedule of Valuation and Qualifying Accounts Disclosure [Text Block] |
SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS AND RESERVES (In Thousands, Except Per Share Data) |  |  |  |  |  |  |  |  |  |
|  |  |  | Column C |  |  |  |  |  |
Column A |  | Column B |  | Charges To |  |  |  | Column D |  | Column E
|  | Balance At |  | Cost |  |  |  |  |  | Balance
|  | Beginning |  | And |  | Other |  |  |  | At End
Description |  | of Period |  | Expense |  | Accounts |  | Deductions |  | of Period
Allowance for doubtful accounts: |  |  |  |  |  |  |  |  |  |
Year ended December 31, 2018 |  | $ | 1,475 |  | $ | — |  | $ | — |  | $ | 575 |  | $ | 900
Year ended December 31, 2017 |  | 1,475 |  | — |  | — |  | — |  | 1,475
Year ended December 31, 2016 |  | 1,475 |  | — |  | — |  | — |  | 1,475
See accompanying Report of Independent Registered Public Accounting Firm.

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- Definition Schedule II Valuation and Qualifying Accounts and Reserves [Abstract] + References No definition available. + Details
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- Definition The entire disclosure for valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 12 -Subsection 09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690 + Details
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