CONDENSED CONSOLIDATING INFORMATION (Unaudited) - Statements of Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Condensed financial statements, captions
Net income (loss)	$ 127,588	$ 80,098
Other comprehensive income (loss):
Foreign currency translation	3,827	12,203
Unrealized gain (loss) on marketable debt securities	9,291	(172)
Derivative instruments	(5,438)	8,615
Other comprehensive income	7,680	20,646
Comprehensive income	135,268	100,744
Comprehensive income attributable to noncontrolling interests	1,803	1,395
Comprehensive income attributable to common stockholders	133,465	99,349
Consolidated Elimination
Condensed financial statements, captions
Net income (loss)	(97,274)	(59,651)
Other comprehensive income (loss):
Foreign currency translation	0	0
Unrealized gain (loss) on marketable debt securities	0	0
Derivative instruments	0	0
Other comprehensive income	0	0
Comprehensive income	(97,274)	(59,651)
Comprehensive income attributable to noncontrolling interests	0	0
Comprehensive income attributable to common stockholders	(97,274)	(59,651)
Ventas, Inc.
Condensed financial statements, captions
Net income (loss)	125,785	78,703
Other comprehensive income (loss):
Foreign currency translation	6,559	12,381
Unrealized gain (loss) on marketable debt securities	0	0
Derivative instruments	0	0
Other comprehensive income	6,559	12,381
Comprehensive income	132,344	91,084
Comprehensive income attributable to noncontrolling interests	0	0
Comprehensive income attributable to common stockholders	132,344	91,084
Ventas Realty
Condensed financial statements, captions
Net income (loss)	(56,030)	(64,301)
Other comprehensive income (loss):
Foreign currency translation	0	0
Unrealized gain (loss) on marketable debt securities	0	0
Derivative instruments	(4,049)	8,021
Other comprehensive income	(4,049)	8,021
Comprehensive income	(60,079)	(56,280)
Comprehensive income attributable to noncontrolling interests	0	0
Comprehensive income attributable to common stockholders	(60,079)	(56,280)
Ventas Subsidiaries
Condensed financial statements, captions
Net income (loss)	155,107	125,347
Other comprehensive income (loss):
Foreign currency translation	(2,732)	(178)
Unrealized gain (loss) on marketable debt securities	9,291	(172)
Derivative instruments	(1,389)	594
Other comprehensive income	5,170	244
Comprehensive income	160,277	125,591
Comprehensive income attributable to noncontrolling interests	1,803	1,395
Comprehensive income attributable to common stockholders	$ 158,474	$ 124,196