FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Asset Derivatives designated as hedging instruments, Fair Value	$ 1,637	$ 272
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	900,280	859,966
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	171,667	149,979
Total assets	174,175	151,730
Debt instruments - fair value
Total liabilities	5,832,248	5,842,034
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	900,280	859,966
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	871	1,479
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	1,637	272
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	174,033	144,160
Total assets	176,541	145,911
Debt instruments - fair value
Total liabilities	5,461,466	5,487,211
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	900,280	859,966
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	871	1,479
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	1,637	272
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	871	1,479
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	871	1,479
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	1,637	272
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	900,280	859,966
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	1,637	272
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	174,033	144,160
Total assets	174,033	144,160
Debt instruments - fair value
Total liabilities	5,461,466	5,487,211
Unsecured Debt \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,405,783	4,406,646
Unsecured Debt \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,079,197	4,092,949
Unsecured Debt \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,079,197	4,092,949
Unsecured Debt \| Working Capital Credit Facility \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	10,968	26,381
Unsecured Debt \| Working Capital Credit Facility \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	10,968	26,381
Unsecured Debt \| Working Capital Credit Facility \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	10,968	26,381
Unsecured Debt \| Commercial Paper \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	480,000	445,000
Unsecured Debt \| Commercial Paper \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	480,000	445,000
Unsecured Debt \| Commercial Paper \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	480,000	445,000
Fixed Rate Debt \| Secured Debt \| Mortgages loans \| Carrying Amount \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	908,497	937,007
Fixed Rate Debt \| Secured Debt \| Mortgages loans \| Estimate of Fair Value \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	864,301	895,881
Fixed Rate Debt \| Secured Debt \| Mortgages loans \| Estimate of Fair Value \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	864,301	895,881
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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