ACCOUNTING POLICIES - Schedule of VIEs (Details) - Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
NHP/PMB L.P.
Variable Interest Entity [Line Items]
Total Assets	$ 614,534	$ 639,763
Total Liabilities	195,529	199,674
Ventas Realty Capital Healthcare Trust Operating Partnership, L.P.
Variable Interest Entity [Line Items]
Total Assets	0	2,143,139
Total Liabilities	0	162,426
Other identified VIEs
Variable Interest Entity [Line Items]
Total Assets	1,950,131	1,882,336
Total Liabilities	335,106	354,034
Tax Credit VIEs
Variable Interest Entity [Line Items]
Total Assets	975,093	981,752
Total Liabilities	$ 230,973	$ 234,109