OTHER ASSETS AND LIABILITIES (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2019
Prepaid Expenses and Other Assets
Straight-line rent	$ 59,082			$ 56,223
Condominium inventory	55,577			56,421
Security, escrow, and other deposits	51,197			17,464
Special Improvement District receivable	42,103			42,996
Intangibles	33,105			33,275
Prepaid expenses	14,132			13,263
Other	8,127			9,252
Tenant incentives and other receivables	7,527			7,556
TIF receivable	3,854			3,931
Federal income tax receivable	2,389			655
Food and beverage and lifestyle inventory	1,914			4,310
Prepaid expenses and other assets, net	332,557			300,373
Increase in prepaid expenses and other assets	32,200
Increase in tenant and other deposits related to increases in land sales deposits	33,700
Increase in condominium inventory	2,900
Increase (decrease) income taxes receivable	1,700
Increase (decrease) food and beverage and lifestyle inventory	(2,400)
Increase (decrease) other assets	(1,100)
Accounts Payable and Accrued Liabilities [Abstract]
Construction payables	240,980			194,794
Condominium deposit liabilities	327,557			261,523
Interest rate swap liabilities	77,363			40,135
Deferred income	63,817			63,483
Accounts payable and accrued expenses	31,651			37,480
Tenant and other deposits	27,632			24,080
Accrued payroll and other employee liabilities	21,697			44,082
Accrued real estate taxes	15,577			27,559
Other	14,101			16,173
Accrued interest	11,418			23,838
Accounts payable and accrued expenses	831,793			733,147
Decrease in accounts payable and accrued expenses	98,600
Decrease in construction payables	66,000
Loss contingency, loss in period	97,900		$ 13,400
Decrease in accrued payroll and other employee liabilities	(22,400)
Decrease in accrued interest	(12,400)
Decrease in accrued real estate taxes	(12,000)
Decrease in accounts payable and accrued expenses	(5,800)
Increase in condominium deposits	46,186	$ (115,774)
Increase in interest rate swap derivative liabilities	37,200
Federal income tax receivable
Prepaid Expenses and Other Assets
Leases	53,059			54,471
Increase (decrease) finite-lived intangible assets, net	(1,400)
Above-market tenant leases
Prepaid Expenses and Other Assets
Leases	491			556
Unsecured Debt
Accounts Payable and Accrued Liabilities [Abstract]
Fixed-rate debt	$ 1,000,000			$ 1,000,000
Interest rate (as a percent)	5.375%
Senior Notes, 5.375% | Senior Notes
Accounts Payable and Accrued Liabilities [Abstract]
Interest rate (as a percent)	5.375%