Real Estate Investments Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Mar. 01, 2017	Sep. 30, 2016
Business Acquisition [Line Items]
Total liabilities assumed	$ 0		$ 0
Equity One Inc. [Member]
Business Acquisition [Line Items]
Land		$ 2,914,790
Building and improvements		2,699,937
Properties in development		68,744
Properties held for sale		19,600
Investments in unconsolidated real estate partnerships		103,566
Real estate assets		5,806,637
Cash, accounts receivable and other assets		112,271
Intangible assets		460,541
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net		302,303
Total assets acquired		6,681,752
Notes payable		757,399
Accounts payable, accrued expenses, and other liabilities		121,441
Lease intangible liabilities		609,807
Total liabilities assumed		1,488,647
Total purchase price		$ 5,193,105