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Number of Model Homes under lease contract.

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The occupancy rate.

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Amount of real estate investments in land acquired during the period.

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No definition available.

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Amount of increase to real estate investments during the period for in-place leases.

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No definition available.

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Amount of increase to real estate investments during the period for leasing costs.

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No definition available.

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Area of a real estate property.

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No definition available.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Aggregate cash payments for a combination of transactions that are classified as investing activities in which assets, which may include securities, other types of investments, or productive assets, are purchased from third-party sellers. This element can be used by entities to aggregate payments for all asset purchases that are classified as investing activities.

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Amount of increase in real estate investments related to improvements for entities with a substantial portion of business acquiring and holding investment real estate.

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Amount of other additions excluding acquisition or improvement to real estate investments for entities with a substantial portion of business acquiring and holding investment real estate.

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Amount of increase (decrease) before accumulated depreciation of real estate investments for entities with a substantial portion of business acquiring and holding investment real estate.

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Definite liabilities to third parties under a termination loan agreement, whether or not guaranteed in whole or in part by the government.

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Real Estate Transactions (Acquisitions of Properties) (Details) (USD $)	12 Months Ended	1 Months Ended
	Dec. 31, 2014	May 31, 2014 sqft	Aug. 31, 2014 sqft	Dec. 31, 2014 sqft	Dec. 31, 2013
Real Estate Properties [Line Items]
Promissory note issued for property acquired	$ 123,899,298us-gaap_NotesPayable			$ 123,899,298us-gaap_NotesPayable	$ 89,551,724us-gaap_NotesPayable
Allocated Purchase Price of Properties Acquired [Abstract]
Land	8,348,830netr_RealEstateAcquisitionsOfLand
Buildings and other	42,279,315us-gaap_RealEstateOtherAdditions
Tenant improvements	4,240,293us-gaap_RealEstateImprovements
In-place leases	2,415,501netr_RealEstateInPlaceLeases
Leasing costs	1,779,430netr_RealEstateLeasingCosts
Total purchase price	59,063,369
Bismarck Office [Member]
Real Estate Properties [Line Items]
Purchase price of property acquired		5,400,000
Cash payment for the properties acquired		2,200,000
Promissory note issued for property acquired	3,321,198	3,400,000		3,321,198	0
Rentable square feet		93,000
Occupancy rate		85.00%
Allocated Purchase Price of Properties Acquired [Abstract]
Land	413,000
Buildings and other	4,233,700
Tenant improvements	474,400
In-place leases	164,300
Leasing costs	64,600
Total purchase price	5,350,000
Union Terrace [Member]
Real Estate Properties [Line Items]
Purchase price of property acquired			9,400,000
Cash payment for the properties acquired			2,800,000
Promissory note issued for property acquired	6,600,000		6,600,000	6,600,000	0
Rentable square feet			84,000
Occupancy rate			82.00%
Allocated Purchase Price of Properties Acquired [Abstract]
Land	1,717,000
Buildings and other	5,267,900
Tenant improvements	1,643,300
In-place leases	370,100
Leasing costs	426,700
Total purchase price	9,425,000
Centennial Tech Center [Member]
Real Estate Properties [Line Items]
Purchase price of property acquired	15,500,000			15,500,000
Cash payment for the properties acquired				5,200,000
Promissory note issued for property acquired	10,250,000			10,250,000	0
Rentable square feet	110,000			110,000
Occupancy rate				97.00%
Allocated Purchase Price of Properties Acquired [Abstract]
Land	2,025,000
Buildings and other	10,417,901
Tenant improvements	1,583,869
In-place leases	762,875
Leasing costs	710,355
Total purchase price	15,500,000
Arapahoe Service Center [Member]
Real Estate Properties [Line Items]
Purchase price of property acquired	11,200,000			11,200,000
Cash payment for the properties acquired				2,400,000
Promissory note issued for property acquired	8,500,000			8,500,000	0
Termination Loans	400,000			400,000
Rentable square feet	44,000			44,000
Occupancy rate				97.00%
Allocated Purchase Price of Properties Acquired [Abstract]
Land	1,750,000
Buildings and other	8,890,316
Tenant improvements	153,392
In-place leases	124,974
Leasing costs	292,987
Total purchase price	11,211,669
Union Town Center [Member]
Real Estate Properties [Line Items]
Purchase price of property acquired	11,800,000			11,800,000
Cash payment for the properties acquired				3,300,000
Promissory note issued for property acquired	8,440,000			8,440,000	0
Rentable square feet	79,000			79,000
Occupancy rate				100.00%
Allocated Purchase Price of Properties Acquired [Abstract]
Land	1,420,000
Buildings and other	8,766,628
Tenant improvements	385,332
In-place leases	993,252
Leasing costs	284,788
Total purchase price	11,850,000
18 Model Home properties Pennsylvania and Arizona [Member]
Real Estate Properties [Line Items]
Purchase price of property acquired	5,700,000			5,700,000
Cash payment for the properties acquired				2,300,000
Promissory note issued for property acquired	3,400,000			3,400,000
Number of Model Homes under lease contract				18
Allocated Purchase Price of Properties Acquired [Abstract]
Land	1,023,830
Buildings and other	4,702,870
Tenant improvements	0
In-place leases	0
Leasing costs	0
Total purchase price	$ 5,726,700