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REAL ESTATE INVESTMENTS AND MINIMUM FUTURE RENTALS (Details) - USD ($) |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Mar. 31, 2015 | Aug. 31, 2017 | Jul. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  | $ 43,150,000 | $ 118,578,000 |
Third Party Real Estate Acquisition Costs |  |  |  |  | 596,000 | $ 449,000
Third Party Real Estate Acquisition Costs |  |  |  | 387,000 |  |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  | 3,531,000 | 35,484,000 |
Building |  |  |  | 35,297,000 | 79,216,000 |
Building Improvements |  |  |  | 858,000 | 1,983,000 |
Intangible Lease Asset |  |  |  | 4,009,000 | 8,194,000 |
Intangible Lease Liability |  |  |  | (158,000) | (6,288,000) |
Total |  |  |  | $ 43,537,000 | $ 118,589,000 |
Weighted average amortization period for intangible lease assets |  |  |  | 6 years 9 months 18 days | 9 years 3 months 18 days |
Weighted average amortization period for intangible lease liabilities |  |  |  | 12 years 2 months 12 days | 13 years |
Above market lease accumulated amortization |  |  |  | $ 17,542,000 | $ 16,074,000 |
Below market lease accumulated amortization |  |  |  | 7,849,000 | 6,386,000 |
Net rental income due to amortization of the above/below market leases |  |  |  | 897,000 | 712,000 | 723,000
Future amortization income of below market leases |  |  |  |  |  |
Deferred rental income |  |  |  | 3,623,000 | 2,379,000 | 1,458,000
Minimum future contractual rents to be received |  |  |  |  |  |
2018 |  |  |  | 64,412,000 |  |
2019 |  |  |  | 62,360,000 |  |
2020 |  |  |  | 60,035,000 |  |
2021 |  |  |  | 56,965,000 |  |
2022 |  |  |  | 47,434,000 |  |
Thereafter |  |  |  | 176,838,000 |  |
Total |  |  |  | 468,044,000 |  |
Unbilled Rent Receivable |  |  |  |  |  |
Unbilled rent receivable |  |  |  | $ 14,125,000 | 13,797,000 |
Period during which amount of unbilled rent receivable is to be billed and received |  |  |  | 24 years |  |
Unbilled straight-line rent receivable written off related to property sold |  |  |  | $ 105,000 | 2,060,000 |
Unbilled rent straight-line rent receivable written off related to tenant filed bankruptcy |  |  |  | 362,000 | 7,000 | 89,000
Unbilled straight-line rent receivable written off related to lease termination fees |  |  |  |  |  | 477,000
Lease Termination Fees |  |  |  |  |  |
Lease termination fee received from tenants in a lease buy-out transaction |  |  |  |  |  | 2,886,000
Write-off of entire balance of the unbilled rent receivable and the intangible lease asset |  |  |  |  |  | 530,000
Purchase of Partner's 50% Interest |  |  |  |  |  |
Purchase of partner's interest in unconsolidated joint venture |  |  |  |  |  | 6,300,000
Rental income |  |  |  |  |  |
Future amortization income of below market leases |  |  |  |  |  |
2018 |  |  |  | 1,794,000 |  |
2019 |  |  |  | 1,781,000 |  |
2020 |  |  |  | 1,629,000 |  |
2021 |  |  |  | 1,593,000 |  |
2022 |  |  |  | 1,468,000 |  |
Thereafter |  |  |  | 9,286,000 |  |
Total |  |  |  | 17,551,000 |  |
Amortization expense |  |  |  |  |  |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Amortization expense relating to origination costs |  |  |  | 4,984,000 | 3,612,000 | $ 3,467,000
Amortization of intangible lease assets |  |  |  |  |  |
2018 |  |  |  | 4,056,000 |  |
2019 |  |  |  | 3,669,000 |  |
2020 |  |  |  | 3,435,000 |  |
2021 |  |  |  | 3,168,000 |  |
2022 |  |  |  | 2,672,000 |  |
Thereafter |  |  |  | 9,232,000 |  |
Total |  |  |  | 26,232,000 |  |
Intangible lease asset - above market lease | Rental income |  |  |  |  |  |
Amortization of intangible lease assets |  |  |  |  |  |
2018 |  |  |  | 748,000 |  |
2019 |  |  |  | 646,000 |  |
2020 |  |  |  | 620,000 |  |
2021 |  |  |  | 614,000 |  |
2022 |  |  |  | 448,000 |  |
Thereafter |  |  |  | 1,217,000 |  |
Total |  |  |  | 4,293,000 |  |
Forbo industrial facility, Huntersville, North Carolina |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  | 8,700,000 |  |
Mortgage incurred |  |  |  | 5,190,000 |  |
Third Party Real Estate Acquisition Costs |  |  |  | 72,000 |  |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  | 1,046,000 |  |
Building |  |  |  | 6,452,000 |  |
Building Improvements |  |  |  | 222,000 |  |
Intangible Lease Asset |  |  |  | 1,052,000 |  |
Total |  |  |  | 8,772,000 |  |
Saddle Creek Logistics industrial facility, Pittston, Pennsylvania |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  | 11,750,000 |  |
Mortgage incurred |  | $ 7,200,000 |  |  |  |
Third Party Real Estate Acquisition Costs |  |  |  | 199,000 |  |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  | 999,000 |  |
Building |  |  |  | 9,675,000 |  |
Building Improvements |  |  |  | 247,000 |  |
Intangible Lease Asset |  |  |  | 1,028,000 |  |
Total |  |  |  | 11,949,000 |  |
Corporate Woods industrial facility, Ankeny, Iowa |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  | 14,700,000 |  |
Mortgage incurred |  |  | $ 8,820,000 |  |  |
Third Party Real Estate Acquisition Costs |  |  |  | 29,000 |  |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  | 1,351,000 |  |
Building |  |  |  | 11,420,000 |  |
Building Improvements |  |  |  | 187,000 |  |
Intangible Lease Asset |  |  |  | 1,929,000 |  |
Intangible Lease Liability |  |  |  | (158,000) |  |
Total |  |  |  | 14,729,000 |  |
Dufresne Spencer Group industrial facility, Memphis, Tennessee |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  | 8,000,000 |  |
Third Party Real Estate Acquisition Costs |  |  |  | 87,000 |  |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  | 135,000 |  |
Building |  |  |  | 7,750,000 |  |
Building Improvements |  |  |  | 202,000 |  |
Total |  |  |  | $ 8,087,000 |  |
Multi-tenant industrial facility, Greenville, South Carolina - 1 |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  |  | 8,100,000 |
Third Party Real Estate Acquisition Costs |  |  |  |  | 80,000 |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  |  | 693,000 |
Building |  |  |  |  | 6,718,000 |
Building Improvements |  |  |  |  | 175,000 |
Intangible Lease Asset |  |  |  |  | 514,000 |
Total |  |  |  |  | 8,100,000 |
Multi-tenant industrial facility, Greenville, South Carolina - 2 |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  |  | 8,950,000 |
Third Party Real Estate Acquisition Costs |  |  |  |  | 81,000 |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  |  | 528,000 |
Building |  |  |  |  | 7,893,000 |
Building Improvements |  |  |  |  | 181,000 |
Intangible Lease Asset |  |  |  |  | 441,000 |
Intangible Lease Liability |  |  |  |  | (93,000) |
Total |  |  |  |  | 8,950,000 |
Toro distribution facility, El Paso, Texas |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  |  | 23,695,000 |
Third Party Real Estate Acquisition Costs |  |  |  |  | 72,000 |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  |  | 3,691,000 |
Building |  |  |  |  | 17,525,000 |
Building Improvements |  |  |  |  | 379,000 |
Intangible Lease Asset |  |  |  |  | 2,100,000 |
Total |  |  |  |  | 23,695,000 |
4 Advanced Auto retail locations, Ohio |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  |  | 6,523,000 |
Third Party Real Estate Acquisition Costs |  |  |  |  | 80,000 |
Mortgage incurred |  |  |  |  | 4,300,000 |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  |  | 653,000 |
Building |  |  |  |  | 5,012,000 |
Building Improvements |  |  |  |  | 189,000 |
Intangible Lease Asset |  |  |  |  | 912,000 |
Intangible Lease Liability |  |  |  |  | (243,000) |
Total |  |  |  |  | 6,523,000 |
The Briarbrook Village Apartments Wheaton, Illinois |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  |  | 10,530,000 |
Third Party Real Estate Acquisition Costs |  |  |  |  | 6,000 |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  |  | 10,536,000 |
Total |  |  |  |  | 10,536,000 |
Burlington Coat and Micro Center retail stores, St. Louis Park, Minnesota |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  |  | 14,150,000 |
Third Party Real Estate Acquisition Costs |  |  |  |  | 74,000 |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  |  | 3,388,000 |
Building |  |  |  |  | 12,632,000 |
Building Improvements |  |  |  |  | 456,000 |
Intangible Lease Asset |  |  |  |  | 651,000 |
Intangible Lease Liability |  |  |  |  | (2,977,000) |
Total |  |  |  |  | 14,150,000 |
The Vue Apartments, Beachwood, Ohio |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  |  | 13,896,000 |
Third Party Real Estate Acquisition Costs |  |  |  |  | 5,000 |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  |  | 13,901,000 |
Total |  |  |  |  | 13,901,000 |
Famous Footwear distribution facility, Lebanon, Tennessee |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Contract purchase price (real estate) |  |  |  |  | 32,734,000 |
Third Party Real Estate Acquisition Costs |  |  |  |  | 195,000 |
Mortgage incurred |  |  |  |  | 21,288,000 |
Allocation of purchase price for the company's real estate acquisitions |  |  |  |  |  |
Land |  |  |  |  | 2,094,000 |
Building |  |  |  |  | 29,436,000 |
Building Improvements |  |  |  |  | 603,000 |
Intangible Lease Asset |  |  |  |  | 3,576,000 |
Intangible Lease Liability |  |  |  |  | (2,975,000) |
Total |  |  |  |  | 32,734,000 |
Represents the retail property located in Lincoln, Nebraska acquired by the entity. |  |  |  |  |  |
Purchase of Partner's 50% Interest |  |  |  |  |  |
Purchase of partner's interest in unconsolidated joint venture | $ 6,300,000 |  |  |  |  |
Contract price directly paid to the partner of unconsolidated joint venture | 2,636,000 |  |  |  |  |
payment made to underlying mortgage of the unconsolidated joint venture | $ 3,664,000 |  |  |  |  |
Represents the retail property located in Lincoln, Nebraska acquired by the entity. | Unconsolidated joint ventures |  |  |  |  |  |
Purchase of Partner's 50% Interest |  |  |  |  |  |
Percentage of equity method investments acquired | 50.00% |  |  |  |  |
Represents the retail property located in Lincoln, Nebraska acquired by the entity. | Consolidated JV |  |  |  |  |  |
Purchase of Partner's 50% Interest |  |  |  |  |  |
Purchase price fair value adjustment | $ 960,000 |  |  |  |  |
Other (n) |  |  |  |  |  |
Real Estate Acquisitions |  |  |  |  |  |
Third Party Real Estate Acquisition Costs |  |  |  |  | $ 14,000 |

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