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Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Accounts Receivables-Allowance for doubtful accounts [Member] |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Year | $ 607 | $ 603 | $ 1,525
Charged to Costs and Expenses | 319 | 368 | (17)
Charged to Other Accounts | 0 | (36) | 235
Deductions | (96) | (328) | (1,140)
Balance at End of Year | 830 | 607 | 603
Allowance for Deferred Rent Receivable [Member] |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Year | 364 | 373 | 1,962
Charged to Costs and Expenses | 0 | 0 | 0
Charged to Other Accounts | (100) | (9) | (1,589)
Deductions | 0 | 0 | 0
Balance at End of Year | 264 | 364 | 373
Allowance for Deferred Tax Asset [Member] |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Year | 1,416 | 2,062 | 2,062
Charged to Costs and Expenses | 668 | (646) | 0
Charged to Other Accounts | 0 | 0 | 0
Deductions | 0 | 0 | 0
Balance at End of Year | $ 2,084 | $ 1,416 | $ 2,062

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- Definition Amount of valuation and qualifying accounts and reserves. + References Reference 1: 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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- Definition Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense. + References Reference 1: 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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