Fair Value Measurements (Schedule of Changes in Property Carrying Values)(Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Jun. 30, 2015	Mar. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Fair value of real estate investments	$ 57,200
Total Loss	19,685		$ 0
Movement in Property, Plant and Equipment [Roll Forward]
Depreciation expense	(76,506)		$ (76,266)
Fair Value, Inputs, Level 3
Schedule of Available-for-sale Securities [Line Items]
Fair value of real estate investments	57,200
Bonita Lakes
Schedule of Available-for-sale Securities [Line Items]
Fair value of real estate investments	28,000
Movement in Property, Plant and Equipment [Roll Forward]
Beginning balance	33,347
Capital expenditures	379
Depreciation expense	(403)
Loss on impairment of real estate	(5,323)
Reclass to investments in unconsolidated affiliates	0
Ending balance	$ 28,000
Percentage of total consolidated revenues	0.70%
Midland Mall
Schedule of Available-for-sale Securities [Line Items]
Fair value of real estate investments	$ 29,200
Total Loss	4,681
Movement in Property, Plant and Equipment [Roll Forward]
Beginning balance	34,195
Capital expenditures	52
Depreciation expense	(366)
Loss on impairment of real estate	(4,681)
Reclass to investments in unconsolidated affiliates	0
Ending balance	$ 29,200
Percentage of total consolidated revenues	0.60%
River Ridge Mall
Schedule of Available-for-sale Securities [Line Items]
Fair value of real estate investments	$ 20,033
Movement in Property, Plant and Equipment [Roll Forward]
Beginning balance	56,610
Capital expenditures	7,106
Depreciation expense	(673)
Net sales proceeds	(33,500)
Loss on impairment of real estate	(9,510)
Reclass to investments in unconsolidated affiliates	(20,033)
Ending balance	$ 0
Percentage of total consolidated revenues	0.60%
Bonita Lakes, Midland Mall and Ridge River Mall
Schedule of Available-for-sale Securities [Line Items]
Total Loss	$ 19,514	$ 19,514
Movement in Property, Plant and Equipment [Roll Forward]
Beginning balance	124,152
Capital expenditures	7,537
Depreciation expense	(1,442)
Net sales proceeds	(33,500)
Loss on impairment of real estate	(19,514)
Reclass to investments in unconsolidated affiliates	(20,033)
Ending balance	$ 57,200