Real Estate Investments, Net - Narrative (Details) $ in Millions	1 Months Ended								3 Months Ended	12 Months Ended
	Dec. 31, 2017 USD ($) facility renewal_option bed	Oct. 31, 2017 USD ($) unit renewal_option facility bed	Sep. 30, 2017 USD ($) unit renewal_option facility bed	Jul. 31, 2017 USD ($) unit renewal_option bed	Jun. 30, 2017 USD ($) unit	May 31, 2017 USD ($) unit renewal_option bed	Mar. 31, 2017 USD ($) renewal_option facility bed	Feb. 28, 2017 USD ($) renewal_option facility bed	Sep. 30, 2017 USD ($) unit facility bed	Dec. 31, 2017 USD ($) facility intangible_asset lease bed	Dec. 31, 2016 facility
Investment [Line Items]
Number of living facilities | facility	188									188
Number of facilities not leased | facility											3
Number of operating leases acquired | lease										3
Remaining term of ground lease										81 years
Off-Market Favorable Lease
Investment [Line Items]
Number of identified intangible assets | intangible_asset										2
Premier Senior Living, LLC
Investment [Line Items]
Number of facilities acquired | facility								2
Number of beds acquired | bed								96
Acquisition consideration								$ 26.1
Leases period								14 years
Lease renewal options | renewal_option								2
Lease renewal term								5 years
Anticipated initial annual lease revenues								$ 2.2
WLC Management Firm LLC
Investment [Line Items]
Number of facilities acquired | facility							5
Number of beds acquired | bed	86			99			455			86
Acquisition consideration	$ 4.6			$ 3.7			$ 29.2
Leases period	14 years			14 years			15 years
Lease renewal options | renewal_option	2			2			2
Lease renewal term	5 years			5 years			5 years
Anticipated initial annual lease revenues	$ 0.4			$ 0.4			$ 2.9
Better Senior Living Consulting LLC
Investment [Line Items]
Number of beds acquired | bed						170
Acquisition consideration						$ 2.0
Leases period						13 years
Lease renewal options | renewal_option						2
Lease renewal term						5 years
Anticipated initial annual lease revenues						$ 0.3
Cascadia Healthcare LLC
Investment [Line Items]
Total number of facilities in staged transaction | facility		7	3						3
Acquisition consideration		$ 65.5
Leases period			13 years			14 years
Lease renewal options | renewal_option			2			2
Lease renewal term			5 years			5 years
Anticipated initial annual lease revenues			$ 5.9			$ 1.1
Cascadia Healthcare LLC | Nampa ID
Investment [Line Items]
Number of units available in living facilities | unit						119
Acquisition consideration						$ 6.5
Cascadia Healthcare LLC | Oregon and Washington
Investment [Line Items]
Number of facilities acquired | facility			2						2
Number of units available in living facilities | unit			129						129
Acquisition consideration									$ 4.9
Cascadia Healthcare LLC | Idaho
Investment [Line Items]
Number of facilities acquired | facility			3						3
Number of beds acquired | bed			236						236
Acquisition consideration			$ 29.8
OnPointe Health LLC
Investment [Line Items]
Acquisition consideration					$ 27.3
Anticipated initial annual lease revenues					2.5
Tenant purchase option					$ 14.3
OnPointe Health LLC | Minimum
Investment [Line Items]
Leases period					17 years
OnPointe Health LLC | Maximum
Investment [Line Items]
Leases period					19 years
OnPointe Health LLC | Brownsville TX
Investment [Line Items]
Number of units available in living facilities | unit					126
OnPointe Health LLC | Albuquerque NM
Investment [Line Items]
Number of units available in living facilities | unit					136
Prelude Home & Services LLC
Investment [Line Items]
Number of units available in living facilities | unit				30
Acquisition consideration				$ 7.8
Leases period				12 years 6 months
Lease renewal options | renewal_option				2
Lease renewal term				5 years
Anticipated initial annual lease revenues				$ 0.6
Priority Management Group LLC
Investment [Line Items]
Number of facilities acquired | facility			3						3
Number of beds acquired | bed			405						405
Acquisition consideration			$ 20.3
Leases period			14 years
Lease renewal options | renewal_option			2
Lease renewal term			5 years
Anticipated initial annual lease revenues			$ 1.9
Five Oaks
Investment [Line Items]
Number of facilities acquired | facility		3
Number of beds acquired | bed		268
Acquisition consideration		$ 12.1
Leases period		14 years
Lease renewal options | renewal_option		2
Lease renewal term		5 years
Anticipated initial annual lease revenues		$ 1.1
Twenty/20 Management Inc
Investment [Line Items]
Number of facilities acquired | facility		3
Number of units available in living facilities | unit		91
Acquisition consideration		$ 18.2
Leases period		12 years
Lease renewal options | renewal_option		2
Lease renewal term		5 years
Anticipated initial annual lease revenues		$ 1.5
Providence Group
Investment [Line Items]
Number of facilities acquired | facility		3
Number of beds acquired | bed		528
Acquisition consideration		$ 69.2
Leases period		15 years
Lease renewal options | renewal_option		2
Lease renewal term		5 years
Anticipated initial annual lease revenues		$ 6.1
Ensign Master Leases
Investment [Line Items]
Facilities subject to operating lease | facility	92									92
Annualized revenues from master leases	$ 57.7									$ 57.7
Escalation factor for calculating revenues after year two	0.00%									0.00%
Percentage change in the consumer price index	2.50%									2.50%
Various Other Operators
Investment [Line Items]
Facilities subject to operating lease | facility	93									93