CONDENSED CONSOLIDATING INFORMATION - Statement of Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Revenues:
Rental income	$ 400,965	$ 357,616	$ 804,161	$ 710,685
Resident fees and services	454,645	374,473	901,559	745,534
Medical office building and other services revenue	9,408	4,367	19,951	10,667
Income from loans and investments	26,068	14,625	48,967	25,392
Equity earnings in affiliates	0	0	0	0
Interest and other income	236	173	708	446
Total revenues	891,322	751,254	1,775,346	1,492,724
Expenses:
Interest	107,591	91,501	214,181	179,342
Depreciation and amortization	249,195	190,818	496,636	384,412
Property-level operating expenses	342,573	288,759	683,284	576,399
Medical office building services costs	5,764	1,626	12,682	4,997
General, administrative and professional fees	33,962	31,306	68,292	64,172
Loss on extinguishment of debt, net	(455)	2,924	(434)	2,665
Merger-related expenses and deal costs	14,585	9,599	49,757	20,359
Other	5,091	4,863	10,387	10,092
Total expenses	758,306	621,396	1,534,785	1,242,438
Income before income (loss) from unconsolidated entities, income taxes, discontinued operations, real estate dispositions and noncontrolling interest	133,016	129,858	240,561	250,286
Income (loss) from unconsolidated entities	9	348	(242)	596
Income tax benefit (expense)	9,789	(3,274)	17,039	(6,707)
Income from continuing operations	142,814	126,932	257,358	244,175
Discontinued operations	67	(255)	(356)	2,776
Gain on real estate dispositions	7,469	11,889	14,155	12,889
Net income	150,350	138,566	271,157	259,840	$ 477,186
Net income attributable to noncontrolling interest	529	168	894	395
Net income attributable to common stockholders	149,821	138,398	270,263	259,445
Ventas, Inc.
Revenues:
Rental income	915	626	1,831	1,244
Resident fees and services	0	0	0	0
Medical office building and other services revenue	0	0	0	0
Income from loans and investments	7,169	931	8,605	1,236
Equity earnings in affiliates	131,119	132,423	261,112	258,510
Interest and other income	20	34	376	185
Total revenues	139,223	134,014	271,924	261,175
Expenses:
Interest	(8,932)	(4,225)	(16,760)	(4,872)
Depreciation and amortization	1,357	1,478	2,700	2,898
Property-level operating expenses	0	0	0	0
Medical office building services costs	0	0	0	0
General, administrative and professional fees	2,821	(12)	80	1,875
Loss on extinguishment of debt, net	0	0	0	(3)
Merger-related expenses and deal costs	11,827	6,482	46,180	8,235
Other	(136)	324	935	1,031
Total expenses	6,937	4,047	33,135	9,164
Income before income (loss) from unconsolidated entities, income taxes, discontinued operations, real estate dispositions and noncontrolling interest	132,286	129,967	238,789	252,011
Income (loss) from unconsolidated entities	0	0	0	0
Income tax benefit (expense)	9,789	(3,274)	17,039	(6,707)
Income from continuing operations	142,075	126,693	255,828	245,304
Discontinued operations	277	(184)	280	1,252
Gain on real estate dispositions	7,469	11,889	14,155	12,889
Net income	149,821	138,398	270,263	259,445
Net income attributable to noncontrolling interest	0	0	0	0
Net income attributable to common stockholders	$ 149,821	138,398	$ 270,263	259,445
Ventas Realty
Condensed financial statements, captions
Ownership percentage	100.00%		100.00%
Revenues:
Rental income	$ 70,959	68,003	$ 142,127	140,615
Resident fees and services	0	0	0	0
Medical office building and other services revenue	0	0	0	0
Income from loans and investments	252	0	303	0
Equity earnings in affiliates	0	0	0	0
Interest and other income	53	5	58	11
Total revenues	71,264	68,008	142,488	140,626
Expenses:
Interest	64,569	46,935	128,163	90,029
Depreciation and amortization	7,677	7,435	16,727	15,406
Property-level operating expenses	73	99	204	248
Medical office building services costs	0	0	0	0
General, administrative and professional fees	5,054	5,520	11,415	11,365
Loss on extinguishment of debt, net	0	0	0	3
Merger-related expenses and deal costs	75	2,110	75	2,110
Other	325	83	327	402
Total expenses	77,773	62,182	156,911	119,563
Income before income (loss) from unconsolidated entities, income taxes, discontinued operations, real estate dispositions and noncontrolling interest	(6,509)	5,826	(14,423)	21,063
Income (loss) from unconsolidated entities	359	320	760	841
Income tax benefit (expense)	0	0	0	0
Income from continuing operations	(6,150)	6,146	(13,663)	21,904
Discontinued operations	(88)	(1,329)	(365)	(774)
Gain on real estate dispositions	0	0	0	0
Net income	(6,238)	4,817	(14,028)	21,130
Net income attributable to noncontrolling interest	0	0	0	0
Net income attributable to common stockholders	$ (6,238)	$ 4,817	$ (14,028)	$ 21,130
Ventas Capital Corporation
Condensed financial statements, captions
Ownership percentage	100.00%	100.00%	100.00%	100.00%	100.00%
Ventas Subsidiaries
Revenues:
Rental income	$ 329,091	$ 288,987	$ 660,203	$ 568,826
Resident fees and services	454,645	374,473	901,559	745,534
Medical office building and other services revenue	9,408	4,367	19,951	10,667
Income from loans and investments	18,647	13,694	40,059	24,156
Equity earnings in affiliates	(62)	48	(140)	211
Interest and other income	163	134	274	250
Total revenues	811,892	681,703	1,621,906	1,349,644
Expenses:
Interest	51,954	48,791	102,778	94,185
Depreciation and amortization	240,161	181,905	477,209	366,108
Property-level operating expenses	342,500	288,660	683,080	576,151
Medical office building services costs	5,764	1,626	12,682	4,997
General, administrative and professional fees	26,087	25,798	56,797	50,932
Loss on extinguishment of debt, net	(455)	2,924	(434)	2,665
Merger-related expenses and deal costs	2,683	1,007	3,502	10,014
Other	4,902	4,456	9,125	8,659
Total expenses	673,596	555,167	1,344,739	1,113,711
Income before income (loss) from unconsolidated entities, income taxes, discontinued operations, real estate dispositions and noncontrolling interest	138,296	126,536	277,167	235,933
Income (loss) from unconsolidated entities	(350)	28	(1,002)	(245)
Income tax benefit (expense)	0	0	0	0
Income from continuing operations	137,946	126,564	276,165	235,688
Discontinued operations	(122)	1,258	(271)	2,298
Gain on real estate dispositions	0	0	0	0
Net income	137,824	127,822	275,894	237,986
Net income attributable to noncontrolling interest	529	168	894	395
Net income attributable to common stockholders	137,295	127,654	275,000	237,591
Consolidated Eliminations
Revenues:
Rental income	0	0	0	0
Resident fees and services	0	0	0	0
Medical office building and other services revenue	0	0	0	0
Income from loans and investments	0	0	0	0
Equity earnings in affiliates	(131,057)	(132,471)	(260,972)	(258,721)
Interest and other income	0	0	0	0
Total revenues	(131,057)	(132,471)	(260,972)	(258,721)
Expenses:
Interest	0	0	0	0
Depreciation and amortization	0	0	0	0
Property-level operating expenses	0	0	0	0
Medical office building services costs	0	0	0	0
General, administrative and professional fees	0	0	0	0
Loss on extinguishment of debt, net	0	0	0	0
Merger-related expenses and deal costs	0	0	0	0
Other	0	0	0	0
Total expenses	0	0	0	0
Income before income (loss) from unconsolidated entities, income taxes, discontinued operations, real estate dispositions and noncontrolling interest	(131,057)	(132,471)	(260,972)	(258,721)
Income (loss) from unconsolidated entities	0	0	0	0
Income tax benefit (expense)	0	0	0	0
Income from continuing operations	(131,057)	(132,471)	(260,972)	(258,721)
Discontinued operations	0	0	0	0
Gain on real estate dispositions	0	0	0	0
Net income	(131,057)	(132,471)	(260,972)	(258,721)
Net income attributable to noncontrolling interest	0	0	0	0
Net income attributable to common stockholders	$ (131,057)	$ (132,471)	$ (260,972)	$ (258,721)