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Real Estate and Intangible Assets - Leasing Activity (Details) | 12 Months Ended
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Dec. 31, 2019 USD ($) ft² property | Dec. 31, 2018 USD ($) ft² property | Dec. 31, 2017 USD ($)
Real Estate Properties [Line Items] |  |  |
Number of leased properties | property | 6 | 3 |
Aggregate Square Footage | ft² | 266,021 | 97,178 |
Annualized GAAP Rent | $ 3,739,000 | $ 1,253,000 |
Tenant Improvement | 2,215,000 | 433,000 |
Leasing Commissions | $ 1,312,000 | 242,000 |
Aggregate Deferred Rent Write Off |  | 200,000 | $ 0
Lease revenue |  | $ 106,798,000 | $ 94,799,000
Lease Contraction or Termination |  |  |
Real Estate Properties [Line Items] |  |  |
Number of leased properties | property | 3 | 2 |
Aggregate Square Footage | ft² | 39,417 | 169,133 |
Aggregate Square Footage Reduced | ft² | 111,309 | 44,032 |
Aggregate Deferred Rent Write Off | $ 0 | $ 184,000 |
Lease revenue | $ 301,000 |  |
Lease revenue |  | $ 559,000 |
Weighted Average |  |  |
Real Estate Properties [Line Items] |  |  |
Lease Term | 9 years 18 days | 6 years 3 months 18 days |
Minimum |  |  |
Real Estate Properties [Line Items] |  |  |
Lease Term | 5 years | 3 years 7 months 6 days |
Maximum |  |  |
Real Estate Properties [Line Items] |  |  |
Lease Term | 11 years 6 months | 7 years |
Columbus, Ohio | Lease Contraction or Termination |  |  |
Real Estate Properties [Line Items] |  |  |
Number of leased properties | property | 1 |  |
Lease revenue | $ 100,000 |  |
Fridley, Minnesota | Lease Contraction or Termination |  |  |
Real Estate Properties [Line Items] |  |  |
Lease revenue | $ 200,000 |  |
Mason, Ohio | Lease Contraction or Termination |  |  |
Real Estate Properties [Line Items] |  |  |
Number of leased properties | property | 1 |  |
Aggregate Square Footage | ft² | 39,417 |  |
Salt Lake City, Utah | Lease Contraction or Termination |  |  |
Real Estate Properties [Line Items] |  |  |
Aggregate Square Footage | ft² |  | 81,271 |
Aggregate Square Footage Reduced | ft² |  | 23,632 |
Aggregate Deferred Rent Write Off |  | $ 100,000 |
Lease revenue |  | $ 300,000 |
Champaign, Illinois | Lease Contraction or Termination |  |  |
Real Estate Properties [Line Items] |  |  |
Aggregate Square Footage | ft² |  | 87,862 |
Aggregate Square Footage Reduced | ft² |  | 20,400 |
Aggregate Deferred Rent Write Off |  | $ 100,000 |
Lease revenue |  | $ 200,000 |

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- Definition Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919372-209981 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=77888421&loc=SL77919311-209978 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 6A -URI http://asc.fasb.org/extlink&oid=118952077&loc=SL77927221-108306 + Details
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