Investments in Real Estate - Schedule of Acquired Properties (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) building	Dec. 31, 2017 USD ($)
Real Estate [Line Items]
Initial Cost Basis	$ 315,590	$ 727,581
Land and Land Estate	30,630	31,930
Building and Improvements	269,019	625,933
Lease in-place Value	26,598	72,508
Below Market Lease	$ (10,657)	$ (2,790)
Leases, Acquired-in-Place [Member]
Real Estate [Line Items]
Weighted-average life of intangible assets (years)	8 years 4 months 24 days	12 years 2 months
Leases, Acquired-in-Place, Market Adjustment [Member]
Real Estate [Line Items]
Weighted-average life of intangible assets (years)	9 years 4 months 24 days	14 years 11 months
Industrial Property [Member] \| Olive Branch, Mississippi [Member] \| Olive Branch, Mississippi, Industrial Property Expiring 2029 [Member]
Real Estate [Line Items]
Initial Cost Basis	$ 44,090
Land and Land Estate	1,958
Building and Improvements	38,687
Lease in-place Value	3,445
Below Market Lease	0
Industrial Property [Member] \| Olive Branch, Mississippi [Member] \| Olive Branch, Mississippi, Industrial Property Expiring 2021 [Member]
Real Estate [Line Items]
Initial Cost Basis	48,575
Land and Land Estate	2,500
Building and Improvements	42,538
Lease in-place Value	5,151
Below Market Lease	(1,614)
Industrial Property [Member] \| Edwardsville, Illinois [Member]
Real Estate [Line Items]
Initial Cost Basis	44,178
Land and Land Estate	3,649
Building and Improvements	41,292
Lease in-place Value	3,467
Below Market Lease	(4,230)
Industrial Property [Member] \| Spartanburg, South Carolina [Member]
Real Estate [Line Items]
Initial Cost Basis	27,632
Land and Land Estate	1,447
Building and Improvements	23,744
Lease in-place Value	2,441
Below Market Lease	0
Industrial Property [Member] \| Pasadena, Texas [Member]
Real Estate [Line Items]
Initial Cost Basis	23,868
Land and Land Estate	4,057
Building and Improvements	17,810
Lease in-place Value	2,001
Below Market Lease	0
Industrial Property [Member] \| Carrollton, Texas [Member]
Real Estate [Line Items]
Initial Cost Basis	19,564
Land and Land Estate	3,228
Building and Improvements	15,766
Lease in-place Value	1,247
Below Market Lease	(677)
Industrial Property [Member] \| Goodyear, Arizona [Member]
Real Estate [Line Items]
Initial Cost Basis	41,372
Land and Land Estate	5,247
Building and Improvements	36,115
Lease in-place Value	2,014
Below Market Lease	(2,004)
Industrial Property [Member] \| Chester, South Carolina [Member]
Real Estate [Line Items]
Initial Cost Basis	66,311
Land and Land Estate	8,544
Building and Improvements	53,067
Lease in-place Value	6,832
Below Market Lease	$ (2,132)
Industrial Property [Member] \| New Century, Kansas [Member]
Real Estate [Line Items]
Initial Cost Basis		$ 12,056
Land and Land Estate		0
Building and Improvements		13,198
Lease in-place Value		1,648
Below Market Lease		(2,790)
Industrial Property [Member] \| Lebanon, Indiana [Member]
Real Estate [Line Items]
Initial Cost Basis		36,194
Land and Land Estate		2,100
Building and Improvements		29,443
Lease in-place Value		4,651
Below Market Lease		0
Industrial Property [Member] \| Cleveland, Tennessee [Member]
Real Estate [Line Items]
Initial Cost Basis		34,400
Land and Land Estate		1,871
Building and Improvements		29,743
Lease in-place Value		2,786
Below Market Lease		0
Industrial Property [Member] \| Grand Prairie, Texas [Member]
Real Estate [Line Items]
Initial Cost Basis		24,317
Land and Land Estate		3,166
Building and Improvements		17,985
Lease in-place Value		3,166
Below Market Lease		0
Industrial Property [Member] \| San Antonio, Texas [Member]
Real Estate [Line Items]
Initial Cost Basis		45,507
Land and Land Estate		1,311
Building and Improvements		36,644
Lease in-place Value		7,552
Below Market Lease		0
Industrial Property [Member] \| Opelika, Alabama [Member]
Real Estate [Line Items]
Initial Cost Basis		37,269
Land and Land Estate		134
Building and Improvements		33,183
Lease in-place Value		3,952
Below Market Lease		0
Industrial Property [Member] \| McDonough, Georgia [Member]
Real Estate [Line Items]
Initial Cost Basis		66,700
Land and Land Estate		5,441
Building and Improvements		52,762
Lease in-place Value		8,497
Below Market Lease		0
Industrial Property [Member] \| Byhalia, Mississippi [Member]
Real Estate [Line Items]
Initial Cost Basis		36,590
Land and Land Estate		1,751
Building and Improvements		31,236
Lease in-place Value		3,603
Below Market Lease		0
Industrial Property [Member] \| Jackson, Tennessee [Member]
Real Estate [Line Items]
Initial Cost Basis		57,920
Land and Land Estate		1,454
Building and Improvements		49,026
Lease in-place Value		7,440
Below Market Lease		0
Industrial Property [Member] \| Smyrna, Tennessee [Member]
Real Estate [Line Items]
Initial Cost Basis		104,890
Land and Land Estate		1,793
Building and Improvements		93,940
Lease in-place Value		9,157
Below Market Lease		0
Industrial Property [Member] \| Lafayette, Indiana [Member]
Real Estate [Line Items]
Initial Cost Basis		17,450
Land and Land Estate		662
Building and Improvements		15,578
Lease in-place Value		1,210
Below Market Lease		0
Industrial Property [Member] \| Romulus, Michigan [Member]
Real Estate [Line Items]
Initial Cost Basis		38,893
Land and Land Estate		2,438
Building and Improvements		33,786
Lease in-place Value		2,669
Below Market Lease		0
Industrial Property [Member] \| Warren, Michigan [Member]
Real Estate [Line Items]
Initial Cost Basis		46,955
Land and Land Estate		972
Building and Improvements		42,521
Lease in-place Value		3,462
Below Market Lease		0
Industrial Property [Member] \| Winchester, Virginia [Member]
Real Estate [Line Items]
Initial Cost Basis		36,700
Land and Land Estate		1,988
Building and Improvements		32,501
Lease in-place Value		2,211
Below Market Lease		0
Office Property [Member] \| Lake Jackson, Texas [Member]
Real Estate [Line Items]
Initial Cost Basis		70,401
Land and Land Estate		3,078
Building and Improvements		67,323
Lease in-place Value		0
Below Market Lease		0
Number of buildings completed \| building	4
Redemption of noncontrolling interests	$ 7,951
Office Property [Member] \| Charlotte, North Carolina [Member]
Real Estate [Line Items]
Initial Cost Basis		61,339
Land and Land Estate		3,771
Building and Improvements		47,064
Lease in-place Value		10,504
Below Market Lease		$ 0

Construction in Progress, Number of Buildings Completed

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- Definition

Investment Building and Building Improvements Acquired During Period

+ References

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
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- Definition

Amount before amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

+ References

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 30
-Paragraph 8
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Balance Type:	credit
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- Definition

This element represents the amount of value allocated by a lessor (acquirer) to lease agreements which exist at acquisition of a leased property. Such amount may include the value assigned to existing tenant relationships and excludes the market adjustment component of the value assigned for above or below-market leases acquired.

+ References

No definition available.

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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
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- Definition

The cash outflow during the period for redemption of redeemable noncontrolling interests.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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