Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Segment Reporting [Abstract]
Number of groups or industry activity segments reported	38		38
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	$ 3,633,063		$ 3,633,063		$ 3,404,878
Total Assets	3,991,053		3,991,053		3,535,590
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	102,367	82,202	199,956	164,614
Other Revenue	259	195	398	301
Total revenue	102,626	82,397	200,354	164,915
Automotive Service [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	104,555		104,555		106,669
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	3,982	4,039	8,098	7,942
Automotive Tire Services [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	192,628		192,628		195,883
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	6,472	5,504	11,980	11,000
Beverages [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	309,576		309,576		302,159
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	5,843	320	11,512	320
Child Care [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	70,210		70,210		73,090
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	5,511	5,476	11,166	10,961
Convenience Stores [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	700,764		700,764		711,667
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	19,439	14,243	38,843	28,435
Drug Stores [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	156,583		156,583		143,739
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	4,035	3,432	7,759	6,863
Health and fitness [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	228,611		228,611		220,653
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	6,255	6,221	12,497	11,754
Restaurants - casual dining [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	479,975		479,975		487,141
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	11,516	11,321	23,100	22,872
Restaurants - quick service [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	244,391		244,391		247,475
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	6,366	6,454	13,195	13,685
Theaters [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	276,415		276,415		281,072
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	7,980	7,563	15,936	15,127
Transportation Services [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	92,671		92,671		4,961
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	2,157	188	2,849	375
All Other Segments [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	776,684		776,684		630,369
Segment Reporting, Revenue Reconciling Item [Line Items]
Rental Revenue	22,811	17,441	43,021	35,280
Net Real Estate Total Segment [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Net real estate Assets	3,633,063		3,633,063		3,404,878
Intangible Assets - Automotive tire services [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	559		559		588
Intangible Assets - Beverages [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	3,700		3,700		0
Intangible Assets - Drug stores [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	14,995		14,995		5,939
Intangible Assets - Health and fitness [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	1,637		1,637		1,708
Intangible Assets - Theaters [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	1,426		1,426		1,579
Intangible Assets - Transportation Services [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	21,614		21,614		0
Intangible Assets - Other -non reportable segments [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	62,620		62,620		16,407
Goodwill - Automotive service [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	1,338		1,338		1,338
Goodwill - Child care [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	5,353		5,353		5,353
Goodwill - Convenience stores [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	2,074		2,074		2,074
Goodwill - Restaurants - casual dining [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	2,461		2,461		2,461
Goodwill - Restaurants - Quick service [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	1,318		1,318		1,318
Goodwill - Other -non-reportable segments [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	4,662		4,662		4,662
Other corporate assets [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total Assets	234,233		234,233		87,285
Unallocated Amount to Segment [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Other Revenue	$ 259	$ 195	$ 398	$ 301