SENIOR NOTES PAYABLE AND OTHER DEBT - Credit Facilities, Commercial Paper, Unsecured Term Loans and Letters of Credit (Details) $ in Millions	1 Months Ended		3 Months Ended
	Apr. 30, 2024 USD ($)	Feb. 29, 2024 CAD ($)	Mar. 31, 2024 USD ($) period	Dec. 31, 2023 USD ($)
Debt instruments
Letters of credit outstanding			$ 15,000,000
Commercial paper program capacity			1,000,000,000
Commercial paper notes			0	$ 0
Unsecured debt | Ventas Realty
Debt instruments
Accordion feature of debt			500,000,000
Unsecured debt			$ 200,000,000
Unsecured debt | SOFR | Ventas Realty
Debt instruments
Variable interest rate			0.95%
Unsecured debt | Revolving Credit Facility
Debt instruments
Maximum borrowing capacity			$ 2,750,000,000
Additional periods | period			2
Additional period term			6 months
Accordion feature of debt			$ 3,750,000,000
Remaining borrowing capacity			2,700,000,000
Fair value of amount outstanding			8,207,000	14,006,000
Letters of credit outstanding			$ 1,200,000
Unsecured debt | Revolving Credit Facility | Subsequent Event
Debt instruments
Maximum borrowing capacity	$ 2,750,000,000
Unsecured debt | Revolving Credit Facility | SOFR
Debt instruments
Variable interest rate			0.925%
Unsecured debt | Revolving Credit Facility | SOFR | Subsequent Event
Debt instruments
Variable interest rate	0.875%
Unsecured debt | Letter of Credit
Debt instruments
Maximum borrowing capacity			$ 100,000,000
Unsecured Term Loan due 2025
Debt instruments
Unsecured debt			0	377,501,000
Repayment and extinguishment of unsecured term loan		$ 500.0	$ 369,400,000
Unsecured Term Loan due 2025 | Canadian Dollar Offered Rate (CDOR)
Debt instruments
Variable interest rate			0.90%
Unsecured term loan due June 2027
Debt instruments
Unsecured debt			$ 500,000,000	$ 500,000,000
Unsecured term loan due June 2027 | Ventas Realty
Debt instruments
Accordion feature of debt			$ 1,250,000,000
Unsecured term loan due June 2027 | SOFR | Ventas Realty
Debt instruments
Variable interest rate			0.95%