Segment Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014 segment	Dec. 31, 2013
Segment Information
Number of activity segments	48us-gaap_NumberOfOperatingSegments
Reconciliation of assets from segment to consolidated
Net real estate	$ 9,781,540o_NetRealEstate	$ 8,796,609o_NetRealEstate
Goodwill	15,470us-gaap_Goodwill	15,660us-gaap_Goodwill
Other corporate assets	175,888o_OtherCorporateAssets	176,713o_OtherCorporateAssets
Total assets	11,012,622us-gaap_Assets	9,924,441us-gaap_Assets
Apparel
Reconciliation of assets from segment to consolidated
Net real estate	188,387	114,126
Intangible assets	52,680	37,553
Automotive service
Reconciliation of assets from segment to consolidated
Net real estate	120,383	118,144
Intangible assets	2,909	3,248
Goodwill	452	454
Automotive tire services
Reconciliation of assets from segment to consolidated
Net real estate	254,857	258,660
Intangible assets	14,871	15,770
Goodwill	865	865
Beverages
Reconciliation of assets from segment to consolidated
Net real estate	302,001	306,278
Intangible assets	2,797	3,055
Child care
Reconciliation of assets from segment to consolidated
Net real estate	54,523	56,599
Goodwill	5,095	5,141
Convenience stores
Reconciliation of assets from segment to consolidated
Net real estate	752,047	766,472
Intangible assets	17,535	13,342
Goodwill	2,023	2,031
Dollar stores
Reconciliation of assets from segment to consolidated
Net real estate	1,165,560	825,729
Intangible assets	58,691	50,209
Drug stores
Reconciliation of assets from segment to consolidated
Net real estate	1,036,697	943,401
Intangible assets	194,905	180,506
Financial services
Reconciliation of assets from segment to consolidated
Net real estate	262,095	252,987
Intangible assets	39,564	40,112
Food processing
Reconciliation of assets from segment to consolidated
Net real estate	133,248	138,000
Intangible assets	22,922	25,297
Grocery stores
Reconciliation of assets from segment to consolidated
Net real estate	338,624	280,047
Intangible assets	46,729	22,073
Health and fitness
Reconciliation of assets from segment to consolidated
Net real estate	546,583	493,981
Intangible assets	66,460	53,703
Health care
Reconciliation of assets from segment to consolidated
Net real estate	227,084	228,491
Intangible assets	35,017	38,465
Home improvement
Reconciliation of assets from segment to consolidated
Net real estate	226,577	121,318
Intangible assets	35,726	18,039
Restaurants - casual dining
Reconciliation of assets from segment to consolidated
Net real estate	450,337	473,527
Intangible assets	10,649	11,906
Goodwill	2,279	2,328
Restaurants - quick service
Reconciliation of assets from segment to consolidated
Net real estate	336,753	312,474
Intangible assets	16,415	17,936
Goodwill	1,085	1,131
Sporting goods
Reconciliation of assets from segment to consolidated
Net real estate	136,110	94,771
Intangible assets	12,311	10,984
Theaters
Reconciliation of assets from segment to consolidated
Net real estate	375,982	367,830
Intangible assets	21,601	23,600
Transportation services
Reconciliation of assets from segment to consolidated
Net real estate	661,053	623,541
Intangible assets	101,040	107,296
Wholesale clubs
Reconciliation of assets from segment to consolidated
Net real estate	465,569	455,875
Intangible assets	39,707	33,221
Other
Reconciliation of assets from segment to consolidated
Net real estate	1,747,070	1,564,358
Intangible assets	247,195	229,144
Goodwill	$ 3,671	$ 3,710
Number of non-reportable segments	28	28

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