Investments in Unconsolidated Joint Ventures - Financial Results (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets:
Property, net	$ 9,241,003	$ 9,052,105
Other assets	703,861	635,838
Total assets	9,944,864	9,687,943
Liabilities and partners' capital:
Mortgage and other notes payable	6,050,930	5,296,594
Other liabilities	388,509	405,052
Company's capital	1,913,475	2,188,057
Outside partners' capital	1,591,950	1,798,240
Total liabilities and partners' capital	9,944,864	9,687,943
Investment in unconsolidated joint ventures:
Company's capital	1,913,475	2,188,057
Basis adjustment	(535,808)	(562,021)
Investments in unconsolidated joint ventures	1,377,667	1,626,036
Assets—Investments in unconsolidated joint ventures	1,492,655	1,709,522
Liabilities—Distributions in excess of investments in unconsolidated joint ventures	(114,988)	(83,486)
Investments in unconsolidated joint ventures	1,377,667	1,626,036
Total assets	9,944,864	9,687,943
Amortization of difference between cost of investments and book value of underlying equity	12,793	16,562	$ 17,610
Revenues:
Minimum rents	638,795	636,182	600,284
Percentage rents	19,736	18,916	20,917
Tenant recoveries	237,295	235,634	235,144
Other	60,751	57,726	56,240
Total revenues	956,577	948,458	912,585
Expenses:
Shopping center and operating expenses	285,935	284,611	274,508
Interest expense	213,032	198,767	187,669
Depreciation and amortization	346,663	352,546	360,378
Total operating expenses	845,630	835,924	822,555
(Loss) gain on sale of assets	14,331	33,825	(375)
Net (loss) income	125,278	146,359	89,655
Company's equity in net (loss) income	71,773	85,546	56,941
PPR Portfolio
Revenues:
Minimum rents	132,258	134,450	129,145
Percentage rents	4,597	5,050	5,437
Tenant recoveries	46,067	46,575	47,856
Other	4,907	5,959	6,303
Total revenues	187,829	192,034	188,741
Expenses:
Shopping center and operating expenses	39,283	41,340	39,804
Interest expense	67,117	67,053	64,626
Depreciation and amortization	97,885	101,625	108,880
Total operating expenses	204,285	210,018	213,310
(Loss) gain on sale of assets	(140)	(36)	0
Net (loss) income	(16,596)	(18,020)	(24,569)
Company's equity in net (loss) income	(16)	(453)	(3,088)
Other Joint Ventures
Revenues:
Minimum rents	506,537	501,732	471,139
Percentage rents	15,139	13,866	15,480
Tenant recoveries	191,228	189,059	187,288
Other	55,844	51,767	49,937
Total revenues	768,748	756,424	723,844
Expenses:
Shopping center and operating expenses	246,652	243,271	234,704
Interest expense	145,915	131,714	123,043
Depreciation and amortization	248,778	250,921	251,498
Total operating expenses	641,345	625,906	609,245
(Loss) gain on sale of assets	14,471	33,861	(375)
Net (loss) income	141,874	164,379	114,224
Company's equity in net (loss) income	71,789	85,999	60,029
Northwestern Mutual Life (NML)
Investment in unconsolidated joint ventures:
Mortgage notes payable to affiliate		482,332
Interest expense on borrowings from related party	20,197	17,898	$ 16,898
Pacific Premier Retail LLC—Various Properties
Assets:
Total assets	3,047,851	3,106,105
Investment in unconsolidated joint ventures:
Total assets	3,047,851	3,106,105
Total liabilities	$ 1,859,637	$ 1,872,227