Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015 segment	Dec. 31, 2014
Segment Information
Number of activity segments	48us-gaap_NumberOfOperatingSegments
Reconciliation of assets from segment to consolidated
Net real estate	$ 9,853,141o_NetRealEstate	$ 9,781,540o_NetRealEstate
Goodwill	15,425us-gaap_Goodwill	15,470us-gaap_Goodwill
Other corporate assets	166,742o_OtherCorporateAssets	175,888o_OtherCorporateAssets
Total assets	11,092,153us-gaap_Assets	11,012,622us-gaap_Assets
Apparel
Reconciliation of assets from segment to consolidated
Net real estate	187,016	188,387
Intangible assets	51,580	52,680
Automotive service industry
Reconciliation of assets from segment to consolidated
Net real estate	131,420	119,684
Intangible assets	20,111	2,909
Goodwill	448	452
Automotive tire services
Reconciliation of assets from segment to consolidated
Net real estate	252,785	254,857
Intangible assets	14,453	14,871
Goodwill	865	865
Beverages
Reconciliation of assets from segment to consolidated
Net real estate	300,932	302,001
Intangible assets	2,732	2,797
Child care
Reconciliation of assets from segment to consolidated
Net real estate	53,647	54,523
Goodwill	5,064	5,095
Convenience stores
Reconciliation of assets from segment to consolidated
Net real estate	746,209	752,047
Intangible assets	17,161	17,535
Goodwill	2,023	2,023
Dollar stores
Reconciliation of assets from segment to consolidated
Net real estate	1,156,416	1,165,560
Intangible assets	57,352	58,691
Drug stores
Reconciliation of assets from segment to consolidated
Net real estate	1,057,256	1,036,697
Intangible assets	197,445	194,905
Financial services
Reconciliation of assets from segment to consolidated
Net real estate	260,145	262,095
Intangible assets	38,330	39,564
Grocery stores
Reconciliation of assets from segment to consolidated
Net real estate	336,052	338,624
Intangible assets	45,719	46,729
Health and fitness
Reconciliation of assets from segment to consolidated
Net real estate	541,941	546,583
Intangible assets	65,189	66,460
Health care
Reconciliation of assets from segment to consolidated
Net real estate	224,982	227,084
Intangible assets	33,750	35,017
Home improvement
Reconciliation of assets from segment to consolidated
Net real estate	229,131	226,577
Intangible assets	36,946	35,726
Restaurants-casual dining
Reconciliation of assets from segment to consolidated
Net real estate	444,247	450,337
Intangible assets	10,335	10,649
Goodwill	2,269	2,279
Restaurants-quick service
Reconciliation of assets from segment to consolidated
Net real estate	376,562	336,753
Intangible assets	21,623	16,415
Goodwill	1,085	1,085
Theaters
Reconciliation of assets from segment to consolidated
Net real estate	375,636	375,982
Intangible assets	20,561	21,601
Transportation services
Reconciliation of assets from segment to consolidated
Net real estate	659,753	661,053
Intangible assets	97,902	101,040
Wholesale clubs
Reconciliation of assets from segment to consolidated
Net real estate	462,317	465,569
Intangible assets	38,834	39,707
Other non-reportable segments
Reconciliation of assets from segment to consolidated
Net real estate	2,056,694	2,017,127
Intangible assets	286,822	282,428
Goodwill	$ 3,671	$ 3,671
Number of non-reportable segments	30	30

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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