Segments (Summary of Segment Operating Results) (Details) ft² in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) ft²	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) ft² segment location	Sep. 30, 2019 USD ($)
Segments reporting
Number of reportable segments | segment			4
Total revenues	$ 154,440	$ 231,172	$ 485,788	$ 1,016,378
Depreciation and amortization	(52,395)	(40,093)	(160,995)	(115,142)
Other income (loss), net	1,284	1,337	(793)	11,798
Equity in earnings (losses) from real estate and other affiliates	266,838	4,542	269,635	20,847
Gain (loss) on sale or disposal of real estate, net	108	24,201	46,232	24,051
Gain (loss) on extinguishment of debt	(13,166)	0	(13,166)	0
Selling profit from sales-type leases	0	13,537	0	13,537
Provision for impairment	0	0	(48,738)	0
Income (loss) before taxes	208,149	38,761	8,020	99,503
Net income (loss)	164,002	30,043	4,817	75,296
Net (income) loss attributable to noncontrolling interests	(24,292)	(285)	(24,325)	(240)
Net income (loss) attributable to common stockholders	139,710	29,758	(19,508)	75,056
Operating Segments
Segments reporting
Total revenues	154,394	231,155	485,637	1,016,361
Total operating expenses	(92,093)	(130,304)	(381,838)	(691,341)
Segment operating income (loss)	62,301	100,851	103,799	325,020
Depreciation and amortization	(50,303)	(37,769)	(155,631)	(109,323)
Interest expense, net	(12,759)	(15,077)	(51,889)	(35,260)
Other income (loss), net	1,707	951	(610)	2,304
Equity in earnings (losses) from real estate and other affiliates	266,838	4,542	269,635	20,847
Gain (loss) on sale or disposal of real estate, net	108	24,201	46,232	24,051
Gain (loss) on extinguishment of debt	(13,166)		(13,166)
Selling profit from sales-type leases		13,537		13,537
Provision for impairment			(48,738)
Income (loss) before taxes	254,726	91,236	149,632	241,176
Corporate expenses and other items
Segments reporting
Corporate income, expenses and other items	(90,724)	(61,193)	(144,815)	(165,880)
Operating Assets
Segments reporting
Total revenues	81,667	104,223	280,201	305,395
Operating Assets | Operating Segments
Segments reporting
Total revenues	81,667	104,223	280,201	305,395
Total operating expenses	(47,590)	(47,950)	(142,052)	(139,589)
Segment operating income (loss)	34,077	56,273	138,149	165,806
Depreciation and amortization	(41,395)	(28,844)	(115,479)	(84,890)
Interest expense, net	(21,045)	(21,645)	(70,341)	(60,695)
Other income (loss), net	(17)	63	150	1,186
Equity in earnings (losses) from real estate and other affiliates	962	441	5,831	3,195
Gain (loss) on sale or disposal of real estate, net	108	0	38,232	0
Gain (loss) on extinguishment of debt	(1,521)		(1,521)
Selling profit from sales-type leases		13,537		13,537
Provision for impairment			(48,738)
Income (loss) before taxes	(28,831)	19,825	(53,717)	38,139
Operating Assets | Operating Segments | Hospitality Revenue
Segments reporting
Total revenues	8,100	20,000	27,900	68,500
Total operating expenses	(7,600)	(14,100)	(24,800)	(46,300)
Master Planned Communities
Segments reporting
Total revenues	52,158	92,287	171,517	216,042
Master Planned Communities | Operating Segments
Segments reporting
Total revenues	52,158	92,287	171,517	216,042
Total operating expenses	(23,059)	(43,697)	(78,751)	(109,676)
Segment operating income (loss)	29,099	48,590	92,766	106,366
Depreciation and amortization	(91)	(88)	(273)	(334)
Interest expense, net	9,176	8,550	26,033	24,376
Other income (loss), net	0	534	0	601
Equity in earnings (losses) from real estate and other affiliates	(1,563)	4,523	4,403	18,859
Gain (loss) on sale or disposal of real estate, net	0	0	0	0
Gain (loss) on extinguishment of debt	0		0
Selling profit from sales-type leases				0
Provision for impairment			0
Income (loss) before taxes	$ 36,621	62,109	$ 122,929	149,868
Seaport District
Segments reporting
Area of real estate property (in sqft) | ft²	453		453
Number of primary locations | location			3
Operating locations | location			2
Total revenues	$ 4,204	23,130	$ 16,170	43,051
Seaport District | Operating Segments
Segments reporting
Total revenues	4,204	23,130	16,170	43,051
Total operating expenses	(11,522)	(27,330)	(34,297)	(59,735)
Segment operating income (loss)	(7,318)	(4,200)	(18,127)	(16,684)
Depreciation and amortization	(7,174)	(6,767)	(34,825)	(19,713)
Interest expense, net	(2,811)	(4,984)	(12,490)	(8,440)
Other income (loss), net	1,590	0	(2,187)	(147)
Equity in earnings (losses) from real estate and other affiliates	(288)	(705)	(8,964)	(1,788)
Gain (loss) on sale or disposal of real estate, net	0	0	0	(6)
Gain (loss) on extinguishment of debt	(11,645)		(11,645)
Selling profit from sales-type leases				0
Provision for impairment			0
Income (loss) before taxes	$ (27,646)	(16,656)	$ (88,238)	(46,778)
Seaport District | Tin Building
Segments reporting
Area of real estate property (in sqft) | ft²	53		53
Strategic Developments
Segments reporting
Total revenues	$ 16,365	11,515	$ 17,749	451,873
Strategic Developments | Operating Segments
Segments reporting
Total revenues	16,365	11,515	17,749	451,873
Total operating expenses	(9,922)	(11,327)	(126,738)	(382,341)
Segment operating income (loss)	6,443	188	(108,989)	69,532
Depreciation and amortization	(1,643)	(2,070)	(5,054)	(4,386)
Interest expense, net	1,921	3,002	4,909	9,499
Other income (loss), net	134	354	1,427	664
Equity in earnings (losses) from real estate and other affiliates	267,727	283	268,365	581
Gain (loss) on sale or disposal of real estate, net	0	24,201	8,000	24,057
Gain (loss) on extinguishment of debt	0		0
Selling profit from sales-type leases				0
Provision for impairment			0
Income (loss) before taxes	$ 274,582	$ 25,958	$ 168,658	$ 99,947