FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 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	$ 16	$ 3,227
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	957,980	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	143,492	247,849
Total assets	144,233	252,357
Debt instruments - fair value
Total liabilities	5,797,019	5,850,636
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	957,980	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	725	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	16	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	141,300	243,546
Total assets	142,041	248,054
Debt instruments - fair value
Total liabilities	5,367,530	5,262,930
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	957,980	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	725	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	16	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	725	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	725	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	16	3,227
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	957,980	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	16	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	141,300	243,546
Total assets	141,300	243,546
Debt instruments - fair value
Total liabilities	5,367,530	5,262,930
Unsecured Debt \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,407,511	4,408,376
Unsecured Debt \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,032,636	3,897,187
Unsecured Debt \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,032,636	3,897,187
Unsecured Debt \| Working capital credit facility \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	30,215	9,361
Unsecured Debt \| Working capital credit facility \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	30,215	9,361
Unsecured Debt \| Working capital credit facility \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	30,215	9,361
Unsecured Debt \| Commercial Paper \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	220,000	289,900
Unsecured Debt \| Commercial Paper \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	220,000	289,900
Unsecured Debt \| Commercial Paper \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	220,000	289,900
Fixed Rate Debt \| Secured Debt \| Mortgages loans \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	1,112,293	1,115,999
Fixed Rate Debt \| Secured Debt \| Mortgages loans \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	1,057,679	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	1,057,679	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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