Earnings From Discontinued Operations (Summary Of Earnings From Discontinued Operations) (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Rental income from operating leases	$ 62,969	$ 52,342	$ 177,864	$ 155,686
Percentage rent	229	196	476	367
Real estate expense reimbursement from tenants	2,440	1,620	6,868	4,865
Interest and other income from real estate transactions	381	601	1,545	2,551
Total revenues	67,460	56,303	191,209	168,439
Gross proceeds				(5,600)
Costs				(4,959)
General and administrative	7,036	5,927	20,261	17,299
Real estate	4,459	2,908	12,055	9,401
Depreciation and amortization	14,947	11,817	42,215	35,422
Total operating expenses	26,442	20,652	74,927	65,970
Interest and other income	457	332	1,083	1,170
Interest expense	(20,086)	(16,501)	(55,260)	(48,524)
Earnings before gain on disposition of real estate and income tax expense	22,228	20,128	63,632	56,701
Total other expenses (revenues)	(19,629)	(16,169)	(54,177)	(47,354)
Gain on disposition of real estate			(38)	(1,013)
Income tax expense	68	170	258	497
Earnings (loss) from discontinued operations including noncontrolling interests	339	1,129	1,036	2,619
Loss (earnings) attributable to noncontrolling interests	(24)	(16)	(24)	361
Real Estate - Investment Portfolio [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Rental income from operating leases	861	731	1,517	1,899
Percentage rent	1	1		14
Real estate expense reimbursement from tenants	18	65	130	204
Interest and other income from real estate transactions			14	63
Total revenues	880	797	1,661	2,180
General and administrative	8	15	1	21
Real estate	126	184	387	429
Depreciation and amortization	55	99	191	366
Impairment losses and other charges	431		431
Total operating expenses	620	298	1,010	816
Earnings before gain on disposition of real estate and income tax expense	260	499	651	1,364
Gain on disposition of real estate	8	635	38	1,013
Income tax expense			(3)	(14)
Earnings from discontinued operations attributable to NNN	268	1,134	686	2,363
Real Estate - Inventory Portfolio [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Rental income from operating leases	490	500	1,629	2,868
Real estate expense reimbursement from tenants	126	113	330	1,254
Interest and other income from real estate transactions	4	13	21	511
Total revenues	620	626	1,980	4,633
Gross proceeds			1,100	37,470
Costs			(998)	(37,170)
Gain loss on sale of other assets			102	300
General and administrative	3	10	11	66
Real estate	133	197	471	1,618
Depreciation and amortization	23	22	66	137
Total operating expenses	159	229	548	1,821
Interest expense	345	385	1,025	2,271
Earnings before gain on disposition of real estate and income tax expense	116	12	509	841
Total other expenses (revenues)	345	385	1,025	2,271
Income tax expense	(45)	(17)	(159)	(585)
Earnings (loss) from discontinued operations including noncontrolling interests	71	(5)	350	256
Loss (earnings) attributable to noncontrolling interests	4	33	(89)	2
Earnings from discontinued operations attributable to NNN	$ 75	$ 28	$ 261	$ 258