SIGNIFICANT ACCOUNTING POLICIES (Details 4) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Acquired Finite-Lived Intangible Assets [Line Items]
Above and below market leases Increase (decrease) rental Income	$ 667,000	$ 529,000	$ 488,000
Amortization expense for in-place lease intangibles	4,204,000	4,535,000	4,210,000
Projected amortization of in-place lease intangibles for the next five years [Abstract]
2019	3,614,000
2020	2,862,000
2021	2,006,000
2022	1,161,000
2023	870,000
2018 Acquisitions (Gwinnett, Eucalyptus, Siempre Viva, Allen Station, Greenhill) [Member]
Acquired operating properties [Abstract]
Total cost of properties purchased	71,086,000
Total purchase price to land	23,263,000
2018 Acquisitions (Gwinnett, Eucalyptus, Siempre Viva, Allen Station, Greenhill) [Member] | Above Market Leases [Member]
Acquired operating properties [Abstract]
Intangibles acquired associated with purchase of Real Estate	21,000
2018 Acquisitions (Gwinnett, Eucalyptus, Siempre Viva, Allen Station, Greenhill) [Member] | Leases, Acquired-in-Place [Member]
Acquired operating properties [Abstract]
Intangibles acquired associated with purchase of Real Estate	4,350,000
2018 Acquisitions (Gwinnett, Eucalyptus, Siempre Viva, Allen Station, Greenhill) [Member] | Below market lease [Member]
Acquired operating properties [Abstract]
Intangibles acquired associated with purchase of Real Estate	1,756,000
2017 Acquisitions (Shiloh 400, Broadmoor, Hurricane Shoals 1 & 2, Southark 5-7) [Member]
Acquired operating properties [Abstract]
Total cost of properties purchased		65,243,000
Total purchase price to land		11,281,000
2017 Acquisitions (Shiloh 400, Broadmoor, Hurricane Shoals 1 & 2, Southark 5-7) [Member] | Above Market Leases [Member]
Acquired operating properties [Abstract]
Intangibles acquired associated with purchase of Real Estate		115,000
2017 Acquisitions (Shiloh 400, Broadmoor, Hurricane Shoals 1 & 2, Southark 5-7) [Member] | Leases, Acquired-in-Place [Member]
Acquired operating properties [Abstract]
Intangibles acquired associated with purchase of Real Estate		3,662,000
2017 Acquisitions (Shiloh 400, Broadmoor, Hurricane Shoals 1 & 2, Southark 5-7) [Member] | Below market lease [Member]
Acquired operating properties [Abstract]
Intangibles acquired associated with purchase of Real Estate		385,000
2016 Acquisitions (Parc North, Flagler, Weston and Jones) [Member]
Acquired operating properties [Abstract]
Total cost of properties purchased			112,158,000
Total amount allocated to real estate properties			22,228,000
Total purchase price to land			29,164,000
2016 Acquisitions (Parc North, Flagler, Weston and Jones) [Member] | Above Market Leases [Member]
Acquired operating properties [Abstract]
Intangibles acquired associated with purchase of Real Estate			393,000
2016 Acquisitions (Parc North, Flagler, Weston and Jones) [Member] | Leases, Acquired-in-Place [Member]
Acquired operating properties [Abstract]
Intangibles acquired associated with purchase of Real Estate			5,941,000
2016 Acquisitions (Parc North, Flagler, Weston and Jones) [Member] | Below market lease [Member]
Acquired operating properties [Abstract]
Intangibles acquired associated with purchase of Real Estate			894,000
Real Estate Properties [Domain] | 2018 Acquisitions (Gwinnett, Eucalyptus, Siempre Viva, Allen Station, Greenhill) [Member]
Acquired operating properties [Abstract]
Total amount allocated to real estate properties	54,537,000
Real Estate Properties [Domain] | 2017 Acquisitions (Shiloh 400, Broadmoor, Hurricane Shoals 1 & 2, Southark 5-7) [Member]
Acquired operating properties [Abstract]
Total amount allocated to real estate properties		51,539,000
Industrial Development [Member] | 2018 Acquisitions (Gwinnett, Eucalyptus, Siempre Viva, Allen Station, Greenhill) [Member]
Acquired operating properties [Abstract]
Total amount allocated to real estate properties	$ 13,934,000
Industrial Development [Member] | 2017 Acquisitions (Shiloh 400, Broadmoor, Hurricane Shoals 1 & 2, Southark 5-7) [Member]
Acquired operating properties [Abstract]
Total amount allocated to real estate properties		$ 10,312,000
Industrial Development [Member] | 2016 Acquisitions (Parc North, Flagler, Weston and Jones) [Member]
Acquired operating properties [Abstract]
Total amount allocated to real estate properties			$ 84,490,000