XML 79 R63.htm IDEA: XBRL DOCUMENT v3.8.0.1
Property (Narrative) (Details)
$ in Thousands
1 Months Ended 3 Months Ended 12 Months Ended
Feb. 29, 2016
center
Dec. 31, 2017
USD ($)
property
Mar. 31, 2017
USD ($)
Sep. 30, 2016
USD ($)
Mar. 31, 2016
USD ($)
Dec. 31, 2017
USD ($)
property
Dec. 31, 2016
USD ($)
property
Dec. 31, 2015
USD ($)
Real Estate [Abstract]                
Number of centers sold 1         18    
Proceeds from sale and disposition of property           $ 446,600    
Gain on sale of property   $ 1,500 $ (3,300) $ 1,100 $ 5,900 218,611 $ 100,714 $ 59,621
Investment in new development projects           $ 57,200    
Number of real estate properties classified as held for sale | property   3       3 1  
Property held for sale   $ 78,700       $ 78,700 $ 1,600