Schedule III - Real Estate and Accumulated Depreciation and Amortization Under Direct Financing Leases (Details) (Direct Financing Lease [Member], USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Barnes and Noble Plantation Fl-direct [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	$ 0
Real Estate and Accumulated Depreciation, Initial Cost of Land	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	3,498
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	[1],[2]
Cvs San Antonio Tx [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Land	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	784
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	[1],[2]
Cvs Amarillo Tx [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Land	159
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	855
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Cvs Lafayette La [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Land	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	949
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	[1],[2]
Cvs Oklahoma City Ok1 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	1,365
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Cvs Oklahoma City, Ok2 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	1,419
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Dennys Stockton Ca [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Land	940
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	509
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Food 4 Less Chula Vista Ca [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Land	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	4,266
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	[1],[2]
Jared Jewelers Phoenix Az [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	95	[3]
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	1,242
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Jared Jewelers Toledo Oh [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	1,458
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Jared Jewelers Oviedo Fl [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	300	[3]
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	1,500
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Jared Jewelers Lewisville Tx [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	155	[3]
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	1,503
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Jared Jewelers Glendale Az [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	1,599
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Kash n Karry Valrico Fl [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Land	1,235
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	3,255
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Logans Roadhouse Martinsburg Wv [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Land	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	1,747
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	[1],[2]
Rite Aid Kennett Square Pa [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	1,984
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Rite Aid Arlington Va [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	3,201
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Sunshine Energy Altamont Ks [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	0
Real Estate and Accumulated Depreciation, Initial Cost of Land	124
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	142
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	0
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Real Estate Held for Investment Under Direct Financing Leases [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate and Accumulated Depreciation, Amount of Encumbrances	550
Real Estate and Accumulated Depreciation, Initial Cost of Land	2,458
Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	29,292
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements	1,984
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0
Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	[1],[2]
Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	0	[1],[2]
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements	0	[1],[2]
Real Estate and Accumulated Depreciation, Accumulated Depreciation	$ 0

[1] As of December 31, 2012, the leases are treated as either operating or financing leases for federal income tax purposes. As of December 31, 2012, the aggregate cost of the properties owned by NNN that are under operating leases were $4,020,556 and financing leases were $4,178.

[2] Transactions in real estate and accumulated depreciation during 2012, 2011, and 2010 are summarized as follows: 2012 2011 2010Land, buildings, and leasehold interests: Balance at the beginning of year$3,531,845 $2,774,947 $2,584,947Acquisitions, completed construction and tenant improvements701,054 772,073 248,438Disposition of land, buildings, and leasehold interests(77,219) (14,744) (58,438)Provision for loss on impairment of real estate10,312 431 —Balance at the close of year$4,145,368 $3,531,845 $2,774,947Accumulated depreciation and amortization: Balance at the beginning of year$270,621 $222,921 $183,949Disposition of land, buildings, and leasehold interests(6,980) (3,010) (2,071)Depreciation and amortization expense70,137 50,710 41,043Balance at the close of year$333,778 $270,621 $222,921

[3] NNN owns only the building for this property, which is encumbered by a fixed rate mortgage and security agreement.