CONDENSED CONSOLIDATING INFORMATION (Unaudited) - Statement of Cash Flows (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Condensed Consolidating Statement of Cash Flows
Net cash provided by (used in) operating activities	$ 737,256	$ 660,736
Cash flows from investing activities:
Net investment in real estate property	(239,498)	(34,453)
Payments to Acquire Loans Receivable	(718,233)	(152,450)
Proceeds from real estate disposals	19,570	63,561
Proceeds from loans receivable	25,067	7,644
Development project expenditures	(143,269)	(69,679)
Capital expenditures	(55,952)	(46,925)
Investment in unconsolidated entities	(39,048)	(4,265)
Net cash used in investing activities	(1,151,363)	(236,567)
Cash flows from financing activities:
Net change in borrowings under revolving credit facility	364,456	24,304
Proceeds from debt	1,028,509	416,217
Repayment of debt	(656,536)	(740,337)
Purchase of noncontrolling interests	(15,809)	(1,604)
Net change in intercompany debt	0	0
Payment of deferred financing costs	(19,687)	(3,844)
Issuance of common stock, net	73,596	377,739
Cash distribution (to) from affiliates	0	0
Cash distribution to common stockholders	(550,965)	(493,471)
Cash distribution to redeemable OP unitholders	(3,720)	(4,437)
Contributions from noncontrolling interests	2,227	5,680
Distributions to noncontrolling interests	(4,156)	(3,582)
Other	9,702	3,622
Net cash provided by (used in) financing activities	227,617	(419,713)
Net (decrease) increase in cash and cash equivalents	(186,490)	4,456
Effect of foreign currency translation on cash and cash equivalents	3,136	(157)
Cash and cash equivalents at beginning of period	286,707	53,023
Cash and cash equivalents at end of period	103,353	57,322
Consolidated Elimination
Condensed Consolidating Statement of Cash Flows
Net cash provided by (used in) operating activities	0	0
Cash flows from investing activities:
Net investment in real estate property	0	0
Payments to Acquire Loans Receivable	0	0
Proceeds from real estate disposals	0	0
Proceeds from loans receivable	0	0
Development project expenditures	0	0
Capital expenditures	0	0
Investment in unconsolidated entities	0	0
Net cash used in investing activities	0	0
Cash flows from financing activities:
Net change in borrowings under revolving credit facility	0	0
Proceeds from debt	0	0
Repayment of debt	0	0
Purchase of noncontrolling interests	0	0
Net change in intercompany debt	0	0
Payment of deferred financing costs	0	0
Issuance of common stock, net	0	0
Cash distribution (to) from affiliates	0	0
Cash distribution to common stockholders	0	0
Cash distribution to redeemable OP unitholders	0	0
Contributions from noncontrolling interests	0	0
Distributions to noncontrolling interests	0	0
Other	0	0
Net cash provided by (used in) financing activities	0	0
Net (decrease) increase in cash and cash equivalents	0	0
Effect of foreign currency translation on cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Ventas, Inc.
Condensed Consolidating Statement of Cash Flows
Net cash provided by (used in) operating activities	41,514	40,671
Cash flows from investing activities:
Net investment in real estate property	(210,120)	(34,453)
Payments to Acquire Loans Receivable	(2,575)	0
Proceeds from real estate disposals	19,570	20,441
Proceeds from loans receivable	21	0
Development project expenditures	0	0
Capital expenditures	0	0
Investment in unconsolidated entities	0	0
Net cash used in investing activities	(193,104)	(14,012)
Cash flows from financing activities:
Net change in borrowings under revolving credit facility	0	0
Proceeds from debt	0	0
Repayment of debt	0	0
Purchase of noncontrolling interests	(15,809)	0
Net change in intercompany debt	795,695	128,165
Payment of deferred financing costs	0	0
Issuance of common stock, net	73,596	377,739
Cash distribution (to) from affiliates	(370,551)	(8,096)
Cash distribution to common stockholders	(550,965)	(493,471)
Cash distribution to redeemable OP unitholders	0	0
Contributions from noncontrolling interests	0	0
Distributions to noncontrolling interests	0	0
Other	9,702	3,622
Net cash provided by (used in) financing activities	(58,332)	7,959
Net (decrease) increase in cash and cash equivalents	(209,922)	34,618
Effect of foreign currency translation on cash and cash equivalents	16,529	(33,353)
Cash and cash equivalents at beginning of period	210,303	11,733
Cash and cash equivalents at end of period	16,910	12,998
Ventas Realty
Condensed Consolidating Statement of Cash Flows
Net cash provided by (used in) operating activities	(61,787)	(45,313)
Cash flows from investing activities:
Net investment in real estate property	0	0
Payments to Acquire Loans Receivable	0	0
Proceeds from real estate disposals	0	0
Proceeds from loans receivable	0	0
Development project expenditures	0	0
Capital expenditures	(15)	(18)
Investment in unconsolidated entities	0	0
Net cash used in investing activities	(15)	(18)
Cash flows from financing activities:
Net change in borrowings under revolving credit facility	453,000	(114,000)
Proceeds from debt	793,904	400,000
Repayment of debt	(300,019)	(555,470)
Purchase of noncontrolling interests	0	0
Net change in intercompany debt	(892,893)	308,816
Payment of deferred financing costs	(18,262)	(3,422)
Issuance of common stock, net	0	0
Cash distribution (to) from affiliates	26,072	9,407
Cash distribution to common stockholders	0	0
Cash distribution to redeemable OP unitholders	0	0
Contributions from noncontrolling interests	0	0
Distributions to noncontrolling interests	0	0
Other	0	0
Net cash provided by (used in) financing activities	61,802	45,331
Net (decrease) increase in cash and cash equivalents	0
Effect of foreign currency translation on cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0
Ventas Subsidiaries
Condensed Consolidating Statement of Cash Flows
Net cash provided by (used in) operating activities	757,529	665,378
Cash flows from investing activities:
Net investment in real estate property	(29,378)	0
Payments to Acquire Loans Receivable	(715,658)	(152,450)
Proceeds from real estate disposals	0	43,120
Proceeds from loans receivable	25,046	7,644
Development project expenditures	(143,269)	(69,679)
Capital expenditures	(55,937)	(46,907)
Investment in unconsolidated entities	(39,048)	4,265
Net cash used in investing activities	(958,244)	(222,537)
Cash flows from financing activities:
Net change in borrowings under revolving credit facility	(88,544)	138,304
Proceeds from debt	234,605	16,217
Repayment of debt	(356,517)	(184,867)
Purchase of noncontrolling interests	0	(1,604)
Net change in intercompany debt	97,198	(436,981)
Payment of deferred financing costs	(1,425)	(422)
Issuance of common stock, net	0	0
Cash distribution (to) from affiliates	344,479	(1,311)
Cash distribution to common stockholders	0	0
Cash distribution to redeemable OP unitholders	(3,720)	(4,437)
Contributions from noncontrolling interests	2,227	5,680
Distributions to noncontrolling interests	(4,156)	(3,582)
Other	0	0
Net cash provided by (used in) financing activities	224,147	(473,003)
Net (decrease) increase in cash and cash equivalents	23,432	(30,162)
Effect of foreign currency translation on cash and cash equivalents	(13,393)	33,196
Cash and cash equivalents at beginning of period	76,404	41,290
Cash and cash equivalents at end of period	$ 86,443	$ 44,324