CONDENSED CONSOLIDATING INFORMATION (Unaudited) - Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Assets
Net real estate investments	$ 20,976,547		$ 20,637,904
Cash and cash equivalents	81,987		72,277
Escrow deposits and restricted cash	56,309		59,187
Investment in and advances to affiliates	0		0
Goodwill	1,050,470		1,050,548
Assets held for sale	1,754		5,454
Other assets	821,844		759,185
Total assets	22,988,911		22,584,555
Liabilities:
Senior notes payable and other debt	10,256,092		10,733,699
Intercompany loans	0		0
Accrued interest	111,388		99,667
Operating lease liabilities	233,757		0
Accounts payable and other liabilities	1,137,980		1,086,030
Liabilities related to assets held for sale	1,216		205
Deferred income taxes	149,454		205,219
Total liabilities	11,889,887		12,124,820
Redeemable OP unitholder and noncontrolling interests	222,662		188,141
Total equity	10,876,362	$ 10,206,013	10,271,594	$ 10,677,569	$ 10,804,044	$ 10,932,185
Total liabilities and equity	22,988,911		22,584,555
Consolidated Elimination
Assets
Net real estate investments	0		0
Cash and cash equivalents	0		0
Escrow deposits and restricted cash	0		0
Investment in and advances to affiliates	(18,566,245)		(18,382,790)
Goodwill	0		0
Assets held for sale	0		0
Other assets	0		0
Total assets	(18,566,245)		(18,382,790)
Liabilities:
Senior notes payable and other debt	0		0
Intercompany loans	0		0
Accrued interest	0		0
Operating lease liabilities	0
Accounts payable and other liabilities	0		0
Liabilities related to assets held for sale	0		0
Deferred income taxes	0		0
Total liabilities	0		0
Redeemable OP unitholder and noncontrolling interests	0		0
Total equity	(18,566,245)		(18,382,790)
Total liabilities and equity	(18,566,245)		(18,382,790)
Ventas, Inc.
Assets
Net real estate investments	3,525		3,598
Cash and cash equivalents	470		6,470
Escrow deposits and restricted cash	2,081		4,211
Investment in and advances to affiliates	15,840,047		15,656,592
Goodwill	0		0
Assets held for sale	0		0
Other assets	80,041		45,989
Total assets	15,926,164		15,716,860
Liabilities:
Senior notes payable and other debt	0		0
Intercompany loans	8,454,178		8,580,896
Accrued interest	(12,038)		(9,953)
Operating lease liabilities	11,918
Accounts payable and other liabilities	323,156		319,753
Liabilities related to assets held for sale	0		0
Deferred income taxes	608		608
Total liabilities	8,777,822		8,891,304
Redeemable OP unitholder and noncontrolling interests	17,923		13,746
Total equity	7,130,419		6,811,810
Total liabilities and equity	15,926,164		15,716,860
Ventas Realty
Assets
Net real estate investments	110,506		112,691
Cash and cash equivalents	0		0
Escrow deposits and restricted cash	128		128
Investment in and advances to affiliates	2,726,198		2,726,198
Goodwill	0		0
Assets held for sale	0		0
Other assets	3,765		4,443
Total assets	2,840,597		2,843,460
Liabilities:
Senior notes payable and other debt	8,139,280		8,620,867
Intercompany loans	(5,046,440)		(5,629,764)
Accrued interest	97,208		85,717
Operating lease liabilities	520
Accounts payable and other liabilities	31,489		19,178
Liabilities related to assets held for sale	0		0
Deferred income taxes	0		0
Total liabilities	3,222,057		3,095,998
Redeemable OP unitholder and noncontrolling interests	0		0
Total equity	(381,460)		(252,538)
Total liabilities and equity	2,840,597		2,843,460
Ventas Subsidiaries
Assets
Net real estate investments	20,862,516		20,521,615
Cash and cash equivalents	81,517		65,807
Escrow deposits and restricted cash	54,100		54,848
Investment in and advances to affiliates	0		0
Goodwill	1,050,470		1,050,548
Assets held for sale	1,754		5,454
Other assets	738,038		708,753
Total assets	22,788,395		22,407,025
Liabilities:
Senior notes payable and other debt	2,116,812		2,112,832
Intercompany loans	(3,407,738)		(2,951,132)
Accrued interest	26,218		23,903
Operating lease liabilities	221,319
Accounts payable and other liabilities	783,335		747,099
Liabilities related to assets held for sale	1,216		205
Deferred income taxes	148,846		204,611
Total liabilities	(109,992)		137,518
Redeemable OP unitholder and noncontrolling interests	204,739		174,395
Total equity	22,693,648		22,095,112
Total liabilities and equity	$ 22,788,395		$ 22,407,025