Line of Credit Payable	3 Months Ended
Mar. 31, 2021
Debt Disclosure [Abstract]
Line of Credit Payable	Line of Credit Payable:NNN's $900,000,000 unsecured revolving credit facility (the "Credit Facility") had no weighted average outstanding balance during the quarter ended March 31, 2021. The Credit Facility matures January 2022, unless the Company exercises its option to extend maturity to January 2023. The Credit Facility bears interest at LIBOR plus 87.5 basis points; however, such interest rate may change pursuant to a tiered interest rate structure based on NNN's debt rating. The Credit Facility also includes an accordion feature which permits NNN to increase the facility size up to $1,600,000,000, subject to lender approval. As of March 31, 2021, there was no outstanding balance and $900,000,000 was available for future borrowings under the Credit Facility, and NNN was in compliance with each of the financial covenants.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI http://asc.fasb.org/topic&trid=2208564

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