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Summary of Significant Accounting Policies - Narrative (Details) | Mar. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Jan. 01, 2019 lease_option
--- | --- | --- | ---
Significant Accounting Policies [Line Items] |  |  |
Accounts receivable, net representing rental income accrued | $ 42,400,000 | $ 42,100,000 |
Right-of-use asset | 1,400,000 |  |
Operating lease liability | 1,500,000 |  |
Minimum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Allowance for doubtful accounts receivables representing rental income accrued | $ 36,900 | $ 30,000 |
Operating lease term of contract | 1 year |  |
Maximum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Operating lease term of contract | 15 years |  |
Corporate Headquarters |  |  |
Significant Accounting Policies [Line Items] |  |  |
Number of options to extend lease | lease_option |  |  | 1
Lease renewal term |  |  | 5 years

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- Definition For an unclassified balance sheet, the amount of fees and other revenue, excluding investment income receivable, earned but not yet received, which were recognized in conformity with revenue recognition criteria based on estimates or specific contractual terms. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980 + Details
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