FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Asset Derivatives designated as hedging instruments, Fair Value	$ 272	$ 3,227
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	859,966	1,017,355
Transfers between levels of fair value hierarchy	0	0
Carrying Amount \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	149,979	247,849
Total assets	151,730	252,357
Debt instruments - fair value
Total liabilities	5,842,034	5,850,636
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	859,966	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	1,479	1,281
Carrying Amount \| Interest rate products \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Asset Derivatives designated as hedging instruments, Fair Value	272	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	144,160	243,546
Total assets	145,911	248,054
Debt instruments - fair value
Total liabilities	5,487,211	5,262,930
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	859,966	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	1,479	1,281
Estimate of Fair Value \| Interest rate products \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Asset Derivatives designated as hedging instruments, Fair Value	272	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	1,479	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	1,479	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	272	3,227
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	859,966	1,017,355
Estimate of Fair Value \| Level 2 \| Interest rate products \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Asset Derivatives designated as hedging instruments, Fair Value	272	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	144,160	243,546
Total assets	144,160	243,546
Debt instruments - fair value
Total liabilities	5,487,211	5,262,930
Unsecured Debt \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,406,646	4,408,376
Unsecured Debt \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,092,949	3,897,187
Unsecured Debt \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,092,949	3,897,187
Unsecured Debt \| Commercial Paper \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	445,000	289,900
Unsecured Debt \| Commercial Paper \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	445,000	289,900
Unsecured Debt \| Commercial Paper \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	445,000	289,900
Unsecured Debt \| Working Capital Credit Facility - 2021 \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	26,381	9,361
Unsecured Debt \| Working Capital Credit Facility - 2021 \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	26,381	9,361
Unsecured Debt \| Working Capital Credit Facility - 2021 \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	26,381	9,361
Fixed Rate Debt \| Secured Debt \| Mortgages loans \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	937,007	1,115,999
Fixed Rate Debt \| Secured Debt \| Mortgages loans \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	895,881	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	895,881	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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Fair value of financial and nonfinancial obligations.

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