Major Tenants	12 Months Ended
Dec. 31, 2017
Risks and Uncertainties [Abstract]
Major Tenants	Major Tenants: As of December 31, 2017, NNN had no tenants that accounted for ten percent or more of its rental and earned income.

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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