Earnings From Discontinued Operations (Summary Of Earnings From Discontinued Operations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Earned income from direct financing leases	$ 566	$ 628
Real estate expense reimbursement from tenants	2,977	2,849
Interest and other income from real estate transactions	384	707
Total revenues	92,565	77,385
General and administrative	8,264	7,604
Real estate	3,954	4,576
Depreciation and amortization	23,755	17,765
Impairment losses and other charges, net of recoveries	2,851	35
Total operating expenses	37,785	29,980
Interest expense	21,827	19,818
Total other expenses (revenues)	21,493	19,460
Earnings from continuing operations before income tax benefit (expense) and equity in earnings of unconsolidated affiliate	33,287	28,107
Income tax expense	780	(115)
Earnings (loss) from discontinued operations attributable to NNN including noncontrolling interests	(164)	1,682
Loss (earnings) attributable to noncontrolling interests	163	8
Segment, Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Rental income from operating leases	539	2,116
Earned income from direct financing leases	0	6
Real estate expense reimbursement from tenants	72	104
Interest and other income from real estate transactions	5	2
Total revenues	616	2,228
General and administrative	2	2
Real estate	30	280
Depreciation and amortization	50	403
Impairment losses and other charges, net of recoveries	1,039	(28)
Total operating expenses	1,121	657
Interest expense	164	184
Total other expenses (revenues)	164	184
Earnings from continuing operations before income tax benefit (expense) and equity in earnings of unconsolidated affiliate	(669)	1,387
Gain on disposition of real estate	505	314
Income tax expense	0	(19)
Loss (earnings) attributable to noncontrolling interests	(56)	(6)
Earnings (loss) from discontinued operations attributable to NNN	$ (220)	$ 1,676