SENIOR NOTES PAYABLE AND OTHER DEBT - Credit Facilities and Unsecured Term Loans (Details) $ in Millions		12 Months Ended
	Sep. 06, 2023 USD ($)	Dec. 31, 2023 USD ($) period	Dec. 31, 2023 CAD ($)	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Long-term debt, gross		$ 13,568,598,000		$ 12,361,244,000
Letters of credit outstanding		15,000,000
Commercial paper program capacity		1,000,000,000
Commercial paper notes		0		403,000,000
Unsecured Debt | Ventas Realty
Debt Instrument [Line Items]
Long-term debt, gross		500,000,000
Debt Instrument, Accordion Limit	$ 500,000,000	1,250,000,000
Unsecured Debt | Secured Overnight Financing Rate (SOFR) | Ventas Realty
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.95%
Unsecured Term Loan due 2025
Debt Instrument [Line Items]
Unsecured debt		$ 377,501,000	$ 500	369,031,000
Unsecured Term Loan due 2025 | Canadian Dollar Offered Rate (CDOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		0.90%
Unsecured term loan due February 2027 | Secured Overnight Financing Rate (SOFR) | Ventas Realty
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		0.95%
3.75% Exchangeable Senior Notes due 2026
Debt Instrument [Line Items]
Interest rate		3.75%	3.75%
Revolving Credit Facility | Unsecured Debt
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 2,750,000,000
Additional periods | period		2
Additional period term		6 months
Accordion feature of debt		$ 3,750,000,000
Line of credit facility, remaining borrowing capacity		2,700,000,000
Letters of credit outstanding		1,200,000
Line of credit facility, amount outstanding		$ 14,006,000		$ 25,230,000
Revolving Credit Facility | Unsecured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		0.925%
Letter of Credit | Unsecured Debt
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 100,000,000