Organization And Summary Of Significant Accounting Policies (Summary Of NNN's Investment Portfolio) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012 states sqft properties	Sep. 30, 2011	Sep. 30, 2012 states sqft properties	Sep. 30, 2011
Accounting Policies [Abstract]
Capitalized interest	$ 336	$ 278	$ 1,204	$ 846
Total properties	1,530		1,530
Gross leasable area (square feet)	18,331,000		18,331,000
States	47		47

Amount of interest capitalized during the period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 34

-Paragraph 21

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Name:	us-gaap_InterestCostsCapitalized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration