Fair Value of Financial Instruments	9 Months Ended
Sep. 30, 2021
Financial Instruments, Owned, at Fair Value [Abstract]
Fair Value of Financial Instruments	Note 7 – Fair Value of Financial Instruments: NNN believes the carrying value of its Credit Facility approximates fair value based upon its nature, terms and variable interest rate. NNN believes that the carrying value of its mortgages payable at September 30, 2021 and December 31, 2020, approximate fair value based upon current market prices of comparable instruments (Level 3). At September 30, 2021 and December 31, 2020, the fair value of NNN’s notes payable net of unamortized discount and excluding debt costs was $4,026,563,000 and $3,532,908,000, respectively, based upon quoted market prices, which is a Level 1 valuation since NNN's notes payable are publicly traded.

The entire disclosure for financial instruments. This disclosure includes, but is not limited to, fair value measurements of short and long term marketable securities, international currencies forward contracts, and auction rate securities. Financial instruments may include hedging and non-hedging currency exchange instruments, derivatives, securitizations and securities available for sale at fair value. Also included are investment results, realized and unrealized gains and losses as well as impairments and risk management disclosures.

No definition available.

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