FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Fair Value
Notes receivable, net	$ 40,128	$ 26,860
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	920,311	$ 1,299,442
Transfers between levels of fair value hierarchy	$ 0
Equity Securities
Debt instruments - fair value
Percentage Of illiquidity discount	15.00%	15.00%
Carrying (Reported) Amount, Fair Value Disclosure \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	$ 40,128	$ 26,860
Total assets	63,909	33,369
Debt instruments - fair value
Total liabilities	5,654,309	5,443,393
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	920,311	1,299,442
Carrying (Reported) Amount, Fair Value Disclosure \| 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	16,117	3,279
Carrying (Reported) Amount, Fair Value Disclosure \| Equity Securities \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Equity securities	7,664	3,230
Estimate of Fair Value, Fair Value Disclosure \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	41,275	27,372
Total assets	65,056	33,881
Debt instruments - fair value
Total liabilities	4,758,062	5,508,491
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	920,311	1,299,442
Estimate of Fair Value, Fair Value Disclosure \| 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	16,117	3,279
Estimate of Fair Value, Fair Value Disclosure \| Equity Securities \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Equity securities	7,664	3,230
Estimate of Fair Value, Fair Value Disclosure \| Level 1 \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	7,664
Estimate of Fair Value, Fair Value Disclosure \| 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	7,664
Estimate of Fair Value, Fair Value Disclosure \| Level 2 \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	16,117	3,279
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	920,311	1,299,442
Estimate of Fair Value, Fair Value Disclosure \| 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	16,117	3,279
Estimate of Fair Value, Fair Value Disclosure \| Level 3 \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	41,275	27,372
Total assets	41,275	30,602
Debt instruments - fair value
Total liabilities	4,758,062	5,508,491
Estimate of Fair Value, Fair Value Disclosure \| Level 3 \| Equity Securities \| Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Equity securities		3,230
Unsecured Debt \| Carrying (Reported) Amount, Fair Value Disclosure \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,131,556	4,133,083
Unsecured Debt \| Estimate of Fair Value, Fair Value Disclosure \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	3,366,736	4,199,363
Unsecured Debt \| Estimate of Fair Value, Fair Value Disclosure \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	3,366,736	4,199,363
Unsecured Debt \| Working capital credit facility \| Carrying (Reported) Amount, Fair Value Disclosure \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	41,181	29,546
Unsecured Debt \| Working capital credit facility \| Estimate of Fair Value, Fair Value Disclosure \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	41,181	29,546
Unsecured Debt \| Working capital credit facility \| Estimate of Fair Value, Fair Value Disclosure \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	41,181	29,546
Unsecured Debt \| Commercial Paper \| Carrying (Reported) Amount, Fair Value Disclosure \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	425,000	220,000
Unsecured Debt \| Commercial Paper \| Estimate of Fair Value, Fair Value Disclosure \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	425,000	220,000
Unsecured Debt \| Commercial Paper \| Estimate of Fair Value, Fair Value Disclosure \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	425,000	220,000
Fixed Rate Debt \| Secured Debt \| Mortgages Notes Payable \| Carrying (Reported) Amount, Fair Value Disclosure \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	1,029,572	1,033,764
Fixed Rate Debt \| Secured Debt \| Mortgages Notes Payable \| Estimate of Fair Value, Fair Value Disclosure \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	898,145	1,032,582
Fixed Rate Debt \| Secured Debt \| Mortgages Notes Payable \| Estimate of Fair Value, Fair Value Disclosure \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	898,145	1,032,582
Variable Rate Debt \| Secured Debt \| Tax-exempt secured notes payable \| Carrying (Reported) Amount, Fair Value Disclosure \| 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 Disclosure \| 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 Disclosure \| Level 3 \| Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	$ 27,000	$ 27,000

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