Mortgages, Notes and Loans Payable, Net (Narrative) (Details)	1 Months Ended		3 Months Ended		12 Months Ended
	Apr. 30, 2022 USD ($)	Feb. 28, 2022 USD ($) building extension	Mar. 31, 2022 USD ($) extension	Mar. 31, 2021 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)
Mortgages, notes and loans payable
Land, buildings and equipment and developments in progress pledged as collateral			$ 4,800,000,000
Repayments			91,939,000	$ 1,283,512,000
Term loan
Mortgages, notes and loans payable
Outstanding borrowings			242,200,000
Term loan | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Mortgages, notes and loans payable
Proceeds from sale of properties					$ 69,800,000
Special Improvement District bonds | Summerlin
Mortgages, notes and loans payable
Special improvement district bond issued			0
SID Bonds obligations assumed by buyers			0
Construction Loans | Creekside Medical Office Building and the Memorial Hermann Health System
Mortgages, notes and loans payable
Face amount		$ 12,800,000
Debt instrument, term		3 years
Number of extension options | extension		2
Term of extension option		1 year
Interest Rate		2.05%
Number of medical office building | building		2
Long-term debt outstanding			$ 0
Construction Loans | Creekside Medical Office Building and the Memorial Hermann Health System | SOFR
Mortgages, notes and loans payable
Reduces in variable rate		1.85%
Non-recourse Financing | 20/25 Waterway Avenue | Subsequent Event
Mortgages, notes and loans payable
Face amount	$ 19,500,000
Future cost	$ 4,200,000
Debt extension option	1 year
Applicable SOFR Interest rate, term	3 years
Amortization, term	25 years
Non-recourse Financing | 20/25 Waterway Avenue | SOFR | Subsequent Event
Mortgages, notes and loans payable
Interest rate margin	2.50%
$700 Million loan due 2023
Mortgages, notes and loans payable
Face amount					700,000,000
Number of options to increase line of credit | extension			1
Option to increase borrowing capacity			$ 50,000,000
$700 Million loan due 2023 | Revolving Credit Facility
Mortgages, notes and loans payable
Face amount					85,000,000
$700 Million loan due 2023 | Term loan
Mortgages, notes and loans payable
Face amount					615,000,000	$ 615,000,000
$700 Million loan due 2023 | Line of credit | Revolving Credit Facility
Mortgages, notes and loans payable
Outstanding borrowings			$ 0
Term loan
Mortgages, notes and loans payable
Repayments					$ 181,800,000