CONDENSED CONSOLIDATING INFORMATION (Unaudited) - Statements of Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Condensed financial statements, captions
Net income (loss)	$ 615,191	$ 150,184	$ 967,307	$ 442,658	$ 651,490
Other comprehensive income (loss):
Foreign currency translation	5,239	(6,421)	17,607	(39,804)
Unrealized (loss) gain on government-sponsored pooled loan investments	(48)	(92)	(233)	158
Other	(936)	1,094	(620)	(2,403)
Total other comprehensive income (loss)	4,255	(5,419)	16,754	(42,049)	$ (49,969)
Comprehensive income	619,446	144,765	984,061	400,609
Comprehensive income attributable to noncontrolling interests	1,233	732	3,391	1,064
Comprehensive income attributable to common stockholders	618,213	144,033	980,670	399,545
Consolidated Elimination
Condensed financial statements, captions
Net income (loss)	(133,159)	(143,501)	(397,632)	(375,657)
Other comprehensive income (loss):
Foreign currency translation	0	0	0	0
Unrealized (loss) gain on government-sponsored pooled loan investments	0	0	0	0
Other	0	0	0	0
Total other comprehensive income (loss)	0	0	0	0
Comprehensive income	(133,159)	(143,501)	(397,632)	(375,657)
Comprehensive income attributable to noncontrolling interests	0	0	0	0
Comprehensive income attributable to common stockholders	(133,159)	(143,501)	(397,632)	(375,657)
Ventas, Inc.
Condensed financial statements, captions
Net income (loss)	613,958	149,452	963,916	441,594
Other comprehensive income (loss):
Foreign currency translation	0	0	0	0
Unrealized (loss) gain on government-sponsored pooled loan investments	(48)	(92)	(233)	158
Other	0	0	0	0
Total other comprehensive income (loss)	(48)	(92)	(233)	158
Comprehensive income	613,910	149,360	963,683	441,752
Comprehensive income attributable to noncontrolling interests	0	0	0	0
Comprehensive income attributable to common stockholders	613,910	149,360	963,683	441,752
Ventas Realty
Condensed financial statements, captions
Net income (loss)	(41,215)	(28,133)	(112,485)	(91,223)
Other comprehensive income (loss):
Foreign currency translation	0	0	0	0
Unrealized (loss) gain on government-sponsored pooled loan investments	0	0	0	0
Other	0	0	0	0
Total other comprehensive income (loss)	0	0	0	0
Comprehensive income	(41,215)	(28,133)	(112,485)	(91,223)
Comprehensive income attributable to noncontrolling interests	0	0	0	0
Comprehensive income attributable to common stockholders	(41,215)	(28,133)	(112,485)	(91,223)
Ventas Subsidiaries
Condensed financial statements, captions
Net income (loss)	175,607	172,366	513,508	467,944
Other comprehensive income (loss):
Foreign currency translation	5,239	(6,421)	17,607	(39,804)
Unrealized (loss) gain on government-sponsored pooled loan investments	0	0	0	0
Other	(936)	1,094	(620)	(2,403)
Total other comprehensive income (loss)	4,303	(5,327)	16,987	(42,207)
Comprehensive income	179,910	167,039	530,495	425,737
Comprehensive income attributable to noncontrolling interests		732	3,391	1,064
Comprehensive income attributable to common stockholders	$ 178,677	$ 166,307	$ 527,104	$ 424,673