Organization and Summary of Significant Accounting Policies (Summary of NNN's Investment Portfolio) (Details)	12 Months Ended
	Dec. 31, 2021 ft² Property State
Property Portfolio:
Total properties | Property	3,223
Gross leasable area (square feet) | ft²	32,753,000
States | State	48
Weighted average remaining lease term (years)	10 years 7 months 6 days