Investments in Unconsolidated Joint Ventures - Combined Condensed Statements of Operations of Unconsolidated Joint Ventures (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenues:
Leasing revenue	$ 179,535	$ 210,721
Total revenues	190,424	226,952
Expenses:
Leasing expenses	5,166	7,425
Interest Expense	53,896	8,074
Depreciation and amortization	78,396	82,213
Total expenses	236,543	191,482
Gain on sale or write down of assets, net	(21,283)	(36,703)
Net (loss) income	(67,730)	8,731
Company's equity in net (loss) income	1,910	9,698
Other
Revenues:
Revenues	5,321	9,258
Shopping center and operating expenses
Expenses:
Operating expenses	76,155	70,725
Joint Venture
Revenues:
Leasing revenue	186,090	230,623
Total revenues	203,149	237,562
Expenses:
Leasing expenses	1,756	1,768
Interest Expense	53,016	54,235
Depreciation and amortization	90,847	96,978
Total expenses	213,826	224,132
Gain on sale or write down of assets, net	54
Net (loss) income	(10,623)	13,430
Company's equity in net (loss) income	1,910	9,698
Joint Venture | Other
Revenues:
Revenues	17,059	6,939
Joint Venture | Shopping center and operating expenses
Expenses:
Operating expenses	68,207	71,151
Joint Venture | PPR Portfolio
Expenses:
Gain on sale or write down of assets, net	0
Company's equity in net (loss) income	(5,507)	4,721
Joint Venture | Other Joint Ventures
Expenses:
Gain on sale or write down of assets, net	54
Company's equity in net (loss) income	7,417	4,977
Joint Venture | PPR Portfolio
Revenues:
Leasing revenue	36,771	58,378
Total revenues	36,865	58,429
Expenses:
Leasing expenses	403	473
Interest Expense	15,803	16,094
Depreciation and amortization	24,307	28,618
Total expenses	49,878	54,827
Net (loss) income	(13,013)	3,602
Joint Venture | PPR Portfolio | Other
Revenues:
Revenues	94	51
Joint Venture | PPR Portfolio | Shopping center and operating expenses
Expenses:
Operating expenses	9,365	9,642
Joint Venture | Other Joint Ventures
Revenues:
Leasing revenue	149,319	172,245
Total revenues	166,284	179,133
Expenses:
Leasing expenses	1,353	1,295
Interest Expense	37,213	38,141
Depreciation and amortization	66,540	68,360
Total expenses	163,948	169,305
Net (loss) income	2,390	9,828
Joint Venture | Other Joint Ventures | Other
Revenues:
Revenues	16,965	6,888
Joint Venture | Other Joint Ventures | Shopping center and operating expenses
Expenses:
Operating expenses	$ 58,842	$ 61,509