Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) facility segment	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Accounting Policies [Abstract]
Number of independent living facilities operated | facility			3
Accumulated amortization of deferred financing costs	$ 2,200,000		$ 2,200,000		$ 4,200,000
Reserve against receivables	0		0		0
Stock-based compensation expense	600,000	$ 400,000	1,136,000	$ 868,000
Restricted cash	0		$ 0		$ 0
Number of reportable segments | segment			1
Pristine Master Lease [Member]
Other Commitments [Line Items]
Property taxes and franchise permit fees receivable	3,000,000		$ 3,000,000
Lease Agreements [Member]
Other Commitments [Line Items]
Remaining contractual payments	$ 400,000		$ 400,000