Discontinued Operations and Dispositions of Real Estate (Details)					1 Months Ended								3 Months Ended						12 Months Ended
	Oct. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Apr. 01, 2015	Mar. 29, 2015 USD ($)	Jan. 31, 2017 USD ($) property facility	Dec. 31, 2016 USD ($) property facility	Oct. 31, 2016 USD ($) Asset property facility	May 31, 2016 USD ($)	Apr. 30, 2016	Jan. 31, 2016 USD ($) property facility	Dec. 31, 2015 USD ($)	Mar. 31, 2015 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2016 USD ($) property facility	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Mar. 31, 2015 USD ($) property	Dec. 31, 2016 USD ($) property facility	Dec. 31, 2016 USD ($) property facility	Dec. 31, 2016 USD ($) property item facility	Dec. 31, 2016 USD ($) property facility	Dec. 31, 2016 USD ($) property facility	Dec. 31, 2016 USD ($) property facility	Dec. 31, 2015 USD ($) property item facility	Dec. 31, 2014 USD ($) item	Dec. 31, 2011 USD ($)	Jun. 30, 2015 USD ($)	Feb. 28, 2015 USD ($)	Aug. 29, 2014 USD ($) facility
Dispositions of Real Estate
Gain on sales of real estate, net																								$ 164,698,000	$ 6,377,000	$ 3,288,000
Impairment, net																									108,349,000
Early repayment of secured debt														$ 108,000,000
Loss on debt extinguishment																								46,020,000
Net investment in direct financing leases						$ 752,589,000					$ 750,693,000			$ 752,589,000		$ 750,693,000			$ 752,589,000	$ 752,589,000	$ 752,589,000	$ 752,589,000	$ 752,589,000	752,589,000	750,693,000
Number of facility sales closed | property																				11
Sales price																								$ 62,000,000
Number of properties for which sales contracts entered | facility						33								33					33	33	33	33	33	33
Number of Facilities Acquired | facility																						9
DFL income																								$ 59,580,000	61,000,000	64,441,000
Real estate and other related assets, net						$ 809,000,000								$ 809,000,000					$ 809,000,000	$ 809,000,000	$ 809,000,000	$ 809,000,000	$ 809,000,000	809,000,000
Aggregate carrying value held for sale, net						927,866,000					5,654,326,000			927,866,000		5,654,326,000			927,866,000	927,866,000	927,866,000	927,866,000	927,866,000	927,866,000	5,654,326,000
Number of properties classified as held for sale | property										2
Consideration from sale of a purchase option										$ 311,000,000			$ 269,000,000
Real estate:
Buildings and improvements						11,692,654,000					12,007,071,000			11,692,654,000		12,007,071,000			11,692,654,000	11,692,654,000	11,692,654,000	11,692,654,000	11,692,654,000	11,692,654,000	12,007,071,000
Land						1,881,487,000					1,934,610,000			1,881,487,000		1,934,610,000			1,881,487,000	1,881,487,000	1,881,487,000	1,881,487,000	1,881,487,000	1,881,487,000	1,934,610,000
Accumulated depreciation and amortization						(2,648,930,000)					(2,476,015,000)			(2,648,930,000)		(2,476,015,000)			(2,648,930,000)	(2,648,930,000)	(2,648,930,000)	(2,648,930,000)	(2,648,930,000)	(2,648,930,000)	(2,476,015,000)
Net real estate						11,325,830,000					11,854,242,000			11,325,830,000		11,854,242,000			11,325,830,000	11,325,830,000	11,325,830,000	11,325,830,000	11,325,830,000	11,325,830,000	11,854,242,000
Net investment in direct financing leases						752,589,000					750,693,000			752,589,000		750,693,000			752,589,000	752,589,000	752,589,000	752,589,000	752,589,000	752,589,000	750,693,000
Cash and cash equivalents of continuing operations, end of year						94,730,000					340,442,000			94,730,000		340,442,000			94,730,000	94,730,000	94,730,000	94,730,000	94,730,000	94,730,000	340,442,000	181,916,000
Restricted cash						42,260,000					46,090,000			42,260,000		46,090,000			42,260,000	42,260,000	42,260,000	42,260,000	42,260,000	42,260,000	46,090,000
Intangible assets, net						479,805,000					586,657,000			479,805,000		586,657,000			479,805,000	479,805,000	479,805,000	479,805,000	479,805,000	479,805,000	586,657,000
Other assets, net						711,624,000					794,483,000			711,624,000		794,483,000			711,624,000	711,624,000	711,624,000	711,624,000	711,624,000	711,624,000	794,483,000
Total assets						15,759,265,000					21,449,849,000			15,759,265,000		21,449,849,000			15,759,265,000	15,759,265,000	15,759,265,000	15,759,265,000	15,759,265,000	15,759,265,000	21,449,849,000
Liabilities [Abstract]
Accounts payable and accrued liabilities						417,360,000					430,786,000			417,360,000		430,786,000			417,360,000	417,360,000	417,360,000	417,360,000	417,360,000	417,360,000	430,786,000
Deferred revenue						149,181,000					122,330,000			149,181,000		122,330,000			149,181,000	149,181,000	149,181,000	149,181,000	149,181,000	149,181,000	122,330,000
Total liabilities						$ 9,817,957,000					11,703,532,000			9,817,957,000		11,703,532,000			9,817,957,000	9,817,957,000	9,817,957,000	9,817,957,000	9,817,957,000	9,817,957,000	11,703,532,000
Costs and expenses:
Depreciation and amortization																								(4,890,000)	(5,880,000)	(4,979,000)
Transaction costs																								86,765,000
Impairments, net																									(1,341,399,000)	(35,913,000)
Income tax expense															$ (53,000,000)									(48,181,000)	(796,000)	(756,000)
Net income (loss) from discontinued operations																										28,010,000
Maximum
Dispositions of Real Estate
Federal and state built-in gain tax from assets sold																											$ 2,000,000,000
Spinoff
Costs and expenses:
Transaction costs														(58,000,000)
Brookdale Senior Living
Dispositions of Real Estate
Number of properties disposed | property					1	7
Number of assets sold or transited | Asset							25
Annual rent reallocated							$ 9,600,000
Number of properties classified as held for sale | property							8
HCRMC
Dispositions of Real Estate
Impairment charges for direct financing lease												$ 478,000,000
Net investment in direct financing leases											$ 5,200,000,000					5,200,000,000									$ 5,200,000,000
Number of non-strategic assets involved in sales transaction | property																		50
Number of facility sales closed | property																									22
Sales price																									$ 219,000,000
Reduction in initial net annual rent due to lease amendment				$ 68,000,000
Minimum rent escalation during the initial term (as a percent)			3.00%
Period of extension of initial term of lease			5 years						5 years
Average lease term			16 years
Deferred lease obligation						$ 525,000,000								525,000,000					$ 525,000,000	525,000,000	525,000,000	$ 525,000,000	525,000,000	525,000,000
DFL income																								385,000,000	573,000,000	599,000,000
Cash payments received																								385,000,000	483,000,000	519,000,000
Federal and state built-in gain tax from assets sold, term																											10 years
Intended To Hold The Assets, Term																											10 years
Federal built-in gain tax from assets sold, federal term											5 years
Federal built-in gain tax from assets sold, state term											10 years
Intended to Sell the Assets, Term																			5 years
State built-in gain from assets sold																								47,000,000
Impairments of investments in unconsolidated joint ventures		$ 27,000,000														19,000,000	$ 27,000,000									36,000,000
Carrying value, equity method investments before impairment		48,000,000															48,000,000									75,000,000
Fair value of equity investment		21,000,000															21,000,000									39,000,000
Real estate:
Net investment in direct financing leases											$ 5,200,000,000					5,200,000,000									$ 5,200,000,000
Costs and expenses:
Income tax expense															$ (49,000,000)
Senior housing | Discontinued Operations, Disposed of by Sale
Dispositions of Real Estate
Total consideration for disposition of real estate																										$ 16,000,000
Post-acute/skilled and SH NNN | Discontinued Operations, Disposed of by Sale
Dispositions of Real Estate
Total consideration for disposition of real estate																								130,000,000
Post-acute/skilled
Dispositions of Real Estate
Number of Facilities Acquired | facility																									9
Acquisition of facility																								275,000,000	$ 184,000,000
Post-acute/skilled | Discontinued Operations, Disposed of by Sale
Dispositions of Real Estate
Number of properties disposed																						5				2
Total consideration for disposition of real estate																										$ 22,000,000
Post-acute/skilled | HCRMC
Dispositions of Real Estate
Number of Facilities Acquired | facility																						2
Acquisition of facility																								91,000,000
SH NNN
Dispositions of Real Estate
Net investment in direct financing leases						$ 628,698,000								$ 628,698,000					$ 628,698,000	$ 628,698,000	$ 628,698,000	$ 628,698,000	$ 628,698,000	$ 628,698,000
Number of properties classified as held for sale | property						64								64					64	64	64	64	64	64
Real estate:
Net investment in direct financing leases						$ 628,698,000								$ 628,698,000					$ 628,698,000	$ 628,698,000	$ 628,698,000	$ 628,698,000	$ 628,698,000	$ 628,698,000
SH NNN | Discontinued Operations, Held-for-sale
Dispositions of Real Estate
Number of properties disposed | facility																						64
SH NNN | Discontinued Operations, Disposed of by Sale
Dispositions of Real Estate
Number of properties disposed | item																									9
Total consideration for disposition of real estate																								88,000,000	$ 60,000,000
SH NNN | Brookdale Senior Living
Dispositions of Real Estate
Number of properties disposed | facility							64
Total consideration for disposition of real estate							$ 1,125,000,000
SH NNN One | Discontinued Operations, Disposed of by Sale
Dispositions of Real Estate
Number of properties disposed | facility																						2
SH NNN Two | Discontinued Operations, Disposed of by Sale
Dispositions of Real Estate
Number of properties disposed | facility																						7
Life science
Dispositions of Real Estate
Number of facilities, purchased option exercised on | facility										8
Number of properties disposed | facility					4
Total consideration for disposition of real estate					$ 76,000,000
Life science | Discontinued Operations, Held-for-sale
Dispositions of Real Estate
Real estate and other related assets, net											288,000,000					288,000,000									288,000,000
Aggregate carrying value held for sale, net											314,000,000					314,000,000									$ 314,000,000
Number of properties disposed | facility																						4			4
Life science | Discontinued Operations, Disposed of by Sale
Dispositions of Real Estate
Number of properties disposed | property																				5
Total consideration for disposition of real estate																								386,000,000	$ 51,000,000
Number of Parcels of land | item																									2
SHOP | Discontinued Operations, Disposed of by Sale
Dispositions of Real Estate
Number of properties disposed | facility																						3
Total consideration for disposition of real estate																								41,000,000
SH NNN, Life Science, SHOP | Discontinued Operations, Held-for-sale
Dispositions of Real Estate
Aggregate carrying value held for sale, net						$ 928,000,000								$ 928,000,000					$ 928,000,000	$ 928,000,000	$ 928,000,000	$ 928,000,000	$ 928,000,000	928,000,000
Hospital | Discontinued Operations, Disposed of by Sale
Dispositions of Real Estate
Total consideration for disposition of real estate																										17,000,000
Post-acute/skilled nursing and senior housing
Dispositions of Real Estate
Number of facility sales closed | facility																									7
Medical office | Discontinued Operations, Disposed of by Sale
Dispositions of Real Estate
Number of properties disposed																				3	7
Total consideration for disposition of real estate																								20,000,000	$ 400,000	145,000
HCP/CPA/Brookdale JV
Dispositions of Real Estate
Debt provided								$ 602,000,000
Debt provided by third-party								360,000,000
Debt provided by entity								242,000,000
Proceeds from issuance of debt								480,000,000
Proceeds from note receivable								$ 242,000,000
HCP/CPA/Brookdale JV | RIDEA II
Dispositions of Real Estate
Investment ownership percentage								40.00%
HCRMC
Dispositions of Real Estate
Impairments of investments in unconsolidated joint ventures																								$ 19,000,000
Carrying value, equity method investments											0					0									0
MBK Development JV | SHOP
Dispositions of Real Estate
Investment ownership percentage						50.00%								50.00%					50.00%	50.00%	50.00%	50.00%	50.00%	50.00%
Brookdale Senior Living
Dispositions of Real Estate
Annualized rent reduction							10,500,000
Brookdale Senior Living | CCRC JV | Senior housing
Dispositions of Real Estate
Number of retirement communities contributed to joint venture | facility																														3
Carrying value of properties contributed																														$ 92,000,000
QCP
Dispositions of Real Estate
Proceeds from issuance of debt	$ 1,750,000,000
QCP | Discontinued Operations, Held-for-sale
Revenue:
Rental and related revenues																								$ 22,971,000	27,651,000	27,111,000
Tenant recoveries																								1,233,000	1,464,000	1,029,000
Interest income																										868,000
Total revenues																								408,956,000	601,950,000	627,637,000
Costs and expenses:
Depreciation and amortization																								(4,892,000)	(5,880,000)	(4,979,000)
Operating																								(3,367,000)	(3,697,000)	(3,309,000)
General and administrative																								(67,000)	(57,000)	(410,000)
Transaction costs																								(86,765,000)
Impairments, net																									(1,295,504,000)
Other income, net																								71,000	70,000	85,000
Income (loss) before income taxes and income from and impairments of equity method investment																								313,936,000	(703,118,000)	619,024,000
Income tax expense																								(48,181,000)	(796,000)	(756,000)
Income from equity method investment																									50,723,000	53,175,000
Impairments of equity method investment																									(45,895,000)	(35,913,000)
Net income (loss) from discontinued operations																								265,755,000	(699,086,000)	635,530,000
QCP | Discontinued Operations, Disposed of by Sale
Dispositions of Real Estate
Early repayment of unsecured debt														$ 500,000,000
QCP | Spinoff
Dispositions of Real Estate
Net investment in direct financing leases							5,107,180,000				5,154,316,000					5,154,316,000									5,154,316,000
Real estate:
Buildings and improvements							191,633,000				191,633,000					191,633,000									191,633,000
Land							14,147,000				14,147,000					14,147,000									14,147,000
Accumulated depreciation and amortization							(71,845,000)				(65,319,000)					(65,319,000)									(65,319,000)
Net real estate							133,935,000				140,461,000					140,461,000									140,461,000
Net investment in direct financing leases							5,107,180,000				5,154,316,000					5,154,316,000									5,154,316,000
Cash and cash equivalents of continuing operations, end of year							6,096,000				6,058,000					6,058,000									6,058,000
Restricted cash											14,526,000					14,526,000									14,526,000
Intangible assets, net							18,517,000				17,049,000					17,049,000									17,049,000
Other assets, net							6,620,000				7,790,000					7,790,000									7,790,000
Total assets							5,272,348,000				5,340,200,000					5,340,200,000									5,340,200,000
Liabilities [Abstract]
Accounts payable and accrued liabilities							46,925,000				5,453,000					5,453,000									5,453,000
Deferred revenue							667,000				687,000					687,000									687,000
Total liabilities							47,592,000				6,140,000					6,140,000									6,140,000
Net assets							$ 5,224,756,000				5,334,060,000					5,334,060,000									5,334,060,000
Revenue:
Income from direct financing leases																								384,752,000	572,835,000	598,629,000
DFL Portfolio
Dispositions of Real Estate
DFL income																								13,000,000	15,000,000	$ 19,000,000
DFL Portfolio | HCRMC
Dispositions of Real Estate
Impairment charges for direct financing lease																817,000,000		$ 478,000,000
Net investment in direct financing leases		6,000,000,000									5,200,000,000	6,100,000,000				5,200,000,000	6,000,000,000	6,100,000,000							5,200,000,000				$ 6,600,000,000
Real estate:
Net investment in direct financing leases		$ 6,000,000,000									5,200,000,000	$ 6,100,000,000				5,200,000,000	$ 6,000,000,000	$ 6,100,000,000							5,200,000,000				$ 6,600,000,000
DFL Portfolio | Senior housing
Dispositions of Real Estate
Net investment in direct financing leases						$ 361,000,000					366,000,000			361,000,000		366,000,000			$ 361,000,000	$ 361,000,000	$ 361,000,000	$ 361,000,000	$ 361,000,000	361,000,000	366,000,000
Real estate:
Net investment in direct financing leases						361,000,000					$ 366,000,000			361,000,000		$ 366,000,000			361,000,000	361,000,000	361,000,000	361,000,000	361,000,000	361,000,000	366,000,000
Direct Financing Lease Tranche A [Member] | HCRMC
Dispositions of Real Estate
Deferred lease obligation						$ 275,000,000								275,000,000					$ 275,000,000	$ 275,000,000	$ 275,000,000	$ 275,000,000	$ 275,000,000	$ 275,000,000
Senior Unsecured, 6.00% notes due in 2017
Dispositions of Real Estate
Early repayment of unsecured debt														$ 500,000,000
Senior Unsecured, 6.00% notes due in 2017 | Debt maturing in 2017
Dispositions of Real Estate
Interest rate (as a percent)						6.00%								6.00%					6.00%	6.00%	6.00%	6.00%	6.00%	6.00%
Senior Unsecured, 6.70% notes due in 2018 | Debt maturing in 2018
Dispositions of Real Estate
Early repayment of unsecured debt														$ 600,000,000
Senior Unsecured, 6.70% notes due in 2018 | QCP | Discontinued Operations, Disposed of by Sale | Debt maturing in 2018
Dispositions of Real Estate
Interest rate (as a percent)						6.70%								6.70%					6.70%	6.70%	6.70%	6.70%	6.70%	6.70%
Income approach | DFL Portfolio | Senior housing | HCRMC | Maximum
Fair Value Quantitative Inputs
Range of EBITDAR																									$ 85,000,000
Range of rent coverage ratio																									1.15
Range of real estate capitalization rate																									7.25%
Income approach | DFL Portfolio | Senior housing | HCRMC | Minimum
Fair Value Quantitative Inputs
Range of EBITDAR																									$ 75,000,000
Range of rent coverage ratio																									1.05
Range of real estate capitalization rate																									6.25%
Income approach | DFL Portfolio | Post-acute/skilled | HCRMC
Fair Value Quantitative Inputs
Range of EBITDAR																									$ 435,000,000
Income approach | DFL Portfolio | Post-acute/skilled | HCRMC | Maximum
Fair Value Quantitative Inputs
Range of rent coverage ratio																									1.35
Range of real estate capitalization rate																									8.50%
Income approach | DFL Portfolio | Post-acute/skilled | HCRMC | Minimum
Fair Value Quantitative Inputs
Range of EBITDAR																									$ 385,000,000
Range of rent coverage ratio																									1.25
Range of real estate capitalization rate																									7.50%
Level 2 | Medical office
Real estate:
Buildings and improvements																												$ 400,000
Level 2 | Market approach | DFL Portfolio | Senior housing | HCRMC
Fair Value Quantitative Inputs
Cash flow coverage ratio																									1.05%
Level 2 | Market approach | DFL Portfolio | Post-acute/skilled | HCRMC
Fair Value Quantitative Inputs
Cash flow coverage ratio																									1.25%
Level 3 | Discounted cash flow valuation technique | HCRMC | Maximum
Fair Value Quantitative Inputs
Range of revenue growth rate																									3.00%
Range of occupancy growth rates																									0.20%
Range of operating expense growth rates																							3.10%
Level 3 | Discounted cash flow valuation technique | HCRMC | Minimum
Fair Value Quantitative Inputs
Range of revenue growth rate																									(1.80%)
Range of operating expense growth rates																							(1.10%)
Level 3 | Discounted cash flow valuation technique | HCRMC
Fair Value Quantitative Inputs
Discount Rate																									15.20%	13.70%
Level 3 | Discounted cash flow valuation technique | HCRMC | Maximum
Fair Value Quantitative Inputs
Range of revenue growth rate																										3.50%
Range of occupancy growth rates																										0.20%
Range of operating expense growth rates																										2.80%
Range of earnings multiples																									7.0	7.0
Level 3 | Discounted cash flow valuation technique | HCRMC | Minimum
Fair Value Quantitative Inputs
Range of revenue growth rate																										(0.20%)
Range of occupancy growth rates																									(0.80%)	(0.30%)
Range of operating expense growth rates																										0.60%
Range of earnings multiples																									6.0	6.0