Organization (Details)	Jun. 30, 2012 property
U.S. and Puerto Rico
Owned, developed and managed retail properties:
Number of income-producing properties	325
Number of U.S. states containing property locations	41
U.S. and Puerto Rico | Malls
Owned, developed and managed retail properties:
Number of income-producing properties	161
U.S. and Puerto Rico | Premium Outlet Centers
Owned, developed and managed retail properties:
Number of income-producing properties	60
U.S. and Puerto Rico | Community/Lifestyle Centers
Owned, developed and managed retail properties:
Number of income-producing properties	70
U.S. and Puerto Rico | Other shopping centers or outlet centers
Owned, developed and managed retail properties:
Number of income-producing properties	21
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	8
Japan | Premium Outlet Centers
Owned, developed and managed retail properties:
Number of income-producing properties	8
South Korea
Owned, developed and managed retail properties:
Number of income-producing properties	2
South Korea | Premium Outlet Centers
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
Mexico | Premium Outlet Centers
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
Malaysia | Premium Outlet Centers
Owned, developed and managed retail properties:
Number of income-producing properties	1
Europe
Owned, developed and managed retail properties:
Number of countries	13
Interest in income-producing properties, under joint venture arrangements (as a percent)	28.90%
Europe | Shopping centers | Minimum
Owned, developed and managed retail properties:
Number of income-producing properties	260