Notes Payable - Narrative (Detail)		1 Months Ended	3 Months Ended
	Jul. 31, 2020 USD ($) property	Mar. 31, 2020 seniorHousingCommunity	Mar. 31, 2022 USD ($) seniorHousingCommunity property	Mar. 31, 2021 USD ($) property	Dec. 31, 2021 USD ($)
Debt Instrument [Line Items]
Property and equipment, net			$ 627,844,000		$ 621,199,000
Other assets, net			6,808,000		3,803,000
Gain (loss) on debt			$ (641,000)	$ 46,999,000
Number of properties | seniorHousingCommunity			76
Current portion of note payable, net of deferred loan costs			$ 32,000,000
Fixed mortgage notes payable | Minimum
Debt Instrument [Line Items]
Debt effective interest rate			3.60%
Fixed mortgage notes payable | Maximum
Debt Instrument [Line Items]
Debt effective interest rate			6.30%
Fixed mortgage notes payable | LIBOR
Debt Instrument [Line Items]
Debt instrument, variable rate at period end			0.44%
Debt instrument, basis spread on variable rate			2.14%
Fixed mortgage notes payable | SOFR
Debt Instrument [Line Items]
Debt instrument, variable rate at period end			0.29%
Debt instrument, basis spread on variable rate			3.50%
Notes Payable
Debt Instrument [Line Items]
Property and equipment, net			$ 603,800,000
Refinance Facility | Mortgage Debt
Debt Instrument [Line Items]
Number of communities refinanced | seniorHousingCommunity		10
Finance agreement amount			80,000,000
Amount available as delayed loans			10,000,000
Additional uncommitted amount			40,000,000
Debt instrument, covenant, tangible net worth, amount, minimum			150,000,000
Debt instrument, covenant, liquidity, amount, minimum			13,000,000
Other assets, net			1,500,000
Debt issuance costs, net			2,100,000
Gain (loss) on debt			$ (600,000)
Refinance Facility | Mortgage Debt | Covenant Achievement, Scenario One
Debt Instrument [Line Items]
Limited payment guaranty, percentage of outstanding balance of the refinance facility			0.33
Refinance Facility | Mortgage Debt | Covenant Achievement, Scenario Two
Debt Instrument [Line Items]
Limited payment guaranty, percentage of outstanding balance of the refinance facility			0.25
Refinance Facility | Mortgage Debt | Covenant Achievement, Scenario Three
Debt Instrument [Line Items]
Limited payment guaranty, percentage of outstanding balance of the refinance facility			0.10
Forbearance Agreements
Debt Instrument [Line Items]
Number of properties | property			2
Accrued interest			$ 3,400,000		$ 2,700,000
Fannie Mae Loan | Forbearance Agreements
Debt Instrument [Line Items]
Gain (loss) on debt				$ 47,000,000
Unpaid loans	$ 3,800,000
Number of properties | property	18			3