Subsequent Events (Details)	1 Months Ended	3 Months Ended			6 Months Ended
	Jul. 31, 2015 USD ($) loan	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)
Subsequent Event [Line Items]
Gain on sale of assets			$ 14,173,000	$ 1,925,000	$ 14,930,000	$ 3,079,000
Subsequent Event
Subsequent Event [Line Items]
Stock repurchase program, authorized amount (in shares)	$ 200,000,000
Number of loans retired | loan	4
Madison Plaza | Subsequent Event
Subsequent Event [Line Items]
Gross sales price	$ 5,700,000
Scenario, Forecast | Madison Plaza
Subsequent Event [Line Items]
Gain on sale of assets		$ 2,771,000
Outlet Shoppes of Bluegrass Loans | Construction loans | Subsequent Event
Subsequent Event [Line Items]
Mortgage and other indebtedness amount carrying value	$ 11,320,000
Term of loan (years)	5 years
Outlet Shoppes of Bluegrass Loans | LIBOR | Construction loans | Subsequent Event
Subsequent Event [Line Items]
Loan agreement, basis spread on variable rate	2.50%
Property Loans Maturing in 2015 | Construction loans | Subsequent Event
Subsequent Event [Line Items]
Mortgage and other indebtedness amount carrying value	$ 322,696,000
Number of loans retired | loan	4
Weighted average interest rate (as a percent)	5.00%
Gulf Coast Town Center Debt Due July 2017 | LIBOR | Secured Debt | Subsequent Event
Subsequent Event [Line Items]
Loan agreement, basis spread on variable rate	2.00%