Organization (Details)	Jun. 30, 2013 property	Dec. 31, 2012 property
U.S. and Puerto Rico
Owned, developed and managed retail properties:
Number of income-producing properties	313
Number of U.S. states containing property locations	38
U.S. and Puerto Rico | Malls
Owned, developed and managed retail properties:
Number of income-producing properties	159
U.S. and Puerto Rico | Premium Outlets
Owned, developed and managed retail properties:
Number of income-producing properties	65
U.S. and Puerto Rico | Community/Lifestyle Centers
Owned, developed and managed retail properties:
Number of income-producing properties	64
U.S. and Puerto Rico | Other shopping centers or outlet centers
Owned, developed and managed retail properties:
Number of income-producing properties	12
U.S. and Puerto Rico | The Mills
Owned, developed and managed retail properties:
Number of income-producing properties	13
Japan
Owned, developed and managed retail properties:
Number of income-producing properties	9	8
Japan | Premium Outlets
Owned, developed and managed retail properties:
Number of income-producing properties	9
South Korea
Owned, developed and managed retail properties:
Number of income-producing properties	2	2
South Korea | Premium Outlets
Owned, developed and managed retail properties:
Number of income-producing properties	2
Mexico
Owned, developed and managed retail properties:
Number of income-producing properties	1	1
Mexico | Premium Outlets
Owned, developed and managed retail properties:
Number of income-producing properties	1
Malaysia
Owned, developed and managed retail properties:
Number of income-producing properties	1	1
Malaysia | Premium Outlets
Owned, developed and managed retail properties:
Number of income-producing properties	1
Europe
Owned, developed and managed retail properties:
Interest in income-producing properties, under joint venture arrangements (as a percent)	28.90%
Number of countries	13
Europe | Shopping centers | Minimum
Owned, developed and managed retail properties:
Number of income-producing properties	260