Segment Information - Summary of Information about Company's Reportable Operating Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Segment Reporting Information [Line Items]
Rental income	$ 112,274	$ 200,002	$ 224,495	$ 403,768
Other income	16,383	11,514	35,184	22,816
Business interruption income	0	3,100	0	5,100
Total revenue from operations	128,657	211,516	259,679	426,584
Rental operation expenses	(36,541)	(64,538)	(73,125)	(129,588)
Net operating income (loss)	92,116	146,978	186,554	296,996
Impairment charges	0	(18,060)	(620)	(48,504)
Depreciation and amortization	(40,060)	(72,462)	(82,668)	(146,886)
Interest income	4,521	5,016	9,042	10,357
Other income (expense), net	(85)	(36,255)	68	(97,862)
Unallocated expenses	(36,019)	(62,189)	(71,857)	(119,074)
Hurricane property loss		(224)		(974)
Equity in net income of joint ventures	1,791	3,821	2,834	12,607
(Reserve) adjustment of preferred equity interests, net	(4,634)	1,625	(5,733)	(2,336)
Gain on disposition of real estate, net	213	29,508	16,590	39,519
Income (loss) before tax expense	17,843	(2,242)	54,210	(56,157)
Total gross real estate assets	4,612,131	7,891,867	4,612,131	7,891,867
Notes receivable, net	19,670	19,670	19,670	19,670	$ 19,675
Operating Segments [Member] | Shopping Center [Member]
Segment Reporting Information [Line Items]
Rental income	112,274	199,988	224,495	403,739
Other income	16,383	11,514	35,155	22,816
Total revenue from operations	128,657	211,502	259,650	426,555
Rental operation expenses	(36,534)	(64,538)	(73,118)	(129,588)
Net operating income (loss)	92,123	146,964	186,532	296,967
Impairment charges		(18,060)	(620)	(48,504)
Depreciation and amortization	(40,060)	(72,462)	(82,668)	(146,886)
Interest income		0
Other income (expense), net		0
Unallocated expenses		0
Hurricane property loss		(224)		(974)
Equity in net income of joint ventures	1,791	3,821	2,834	12,607
(Reserve) adjustment of preferred equity interests, net		0
Gain on disposition of real estate, net	213	29,508	16,590	39,519
Income (loss) before tax expense		0
Total gross real estate assets	4,612,131	7,891,867	4,612,131	7,891,867
Operating Segments [Member] | Loan Investments [Member]
Segment Reporting Information [Line Items]
Rental income	0	14	0	29
Other income	0	0	29	0
Total revenue from operations	0	14	29	29
Rental operation expenses	(7)	0	(7)	0
Net operating income (loss)	(7)	14	22	29
Impairment charges		0
Depreciation and amortization		0
Interest income	4,521	5,016	9,042	10,357
Other income (expense), net		0
Unallocated expenses		0
Hurricane property loss		0
Equity in net income of joint ventures		0
(Reserve) adjustment of preferred equity interests, net	(4,634)	1,625	(5,733)	(2,336)
Gain on disposition of real estate, net		0
Income (loss) before tax expense		0
Notes receivable, net	189,983	247,747	189,983	247,747
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Rental income		0
Other income		0
Total revenue from operations		0
Rental operation expenses		0
Net operating income (loss)		0
Impairment charges		0
Depreciation and amortization		0
Interest income		0	0
Other income (expense), net	(85)	(36,255)	68	(97,862)
Unallocated expenses	(36,019)	(62,189)	(71,857)	(119,074)
Hurricane property loss		0
Equity in net income of joint ventures		0
(Reserve) adjustment of preferred equity interests, net		0
Gain on disposition of real estate, net		0
Income (loss) before tax expense		0
Notes receivable, net	$ (170,313)	$ (228,077)	$ (170,313)	$ (228,077)