FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2025	Dec. 31, 2024
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	$ 558	$ 3,227
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	876,127	1,017,355
Transfers between levels of fair value hierarchy	0
Carrying Amount \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	146,749	247,849
Total assets	148,339	252,357
Debt instruments - fair value
Total liabilities	5,856,102	5,850,636
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	876,127	1,017,355
Carrying Amount \| Equity Securities \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Equity securities	1,032	1,281
Carrying Amount \| Interest rate contracts \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	558	3,227
Estimate of Fair Value \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	141,190	243,546
Total assets	142,780	248,054
Debt instruments - fair value
Total liabilities	5,494,696	5,262,930
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	876,127	1,017,355
Estimate of Fair Value \| Equity Securities \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Equity securities	1,032	1,281
Estimate of Fair Value \| Interest rate contracts \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	558	3,227
Estimate of Fair Value \| Level 1 \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	1,032	1,281
Estimate of Fair Value \| Level 1 \| Equity Securities \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Equity securities	1,032	1,281
Estimate of Fair Value \| Level 2 \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	558	3,227
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	876,127	1,017,355
Estimate of Fair Value \| Level 2 \| Interest rate contracts \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	558	3,227
Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	141,190	243,546
Total assets	141,190	243,546
Debt instruments - fair value
Total liabilities	5,494,696	5,262,930
Unsecured Debt \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,407,080	4,408,376
Unsecured Debt \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,093,122	3,897,187
Unsecured Debt \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,093,122	3,897,187
Unsecured Debt \| Working Capital Credit Facility \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	15,686	9,361
Unsecured Debt \| Working Capital Credit Facility \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	15,686	9,361
Unsecured Debt \| Working Capital Credit Facility \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	15,686	9,361
Unsecured Debt \| Commercial Paper \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	340,000	289,900
Unsecured Debt \| Commercial Paper \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	340,000	289,900
Unsecured Debt \| Commercial Paper \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	340,000	289,900
Fixed Rate Debt \| Secured Debt \| Mortgages loans \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	1,066,336	1,115,999
Fixed Rate Debt \| Secured Debt \| Mortgages loans \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	1,018,888	1,039,482
Fixed Rate Debt \| Secured Debt \| Mortgages loans \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	1,018,888	1,039,482
Variable Rate Debt \| Secured Debt \| Tax-exempt secured notes payable \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	27,000	27,000
Variable Rate Debt \| Secured Debt \| Tax-exempt secured notes payable \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	27,000	27,000
Variable Rate Debt \| Secured Debt \| Tax-exempt secured notes payable \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	$ 27,000	$ 27,000

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