Supplemental Disclosure of Cash Flow Information - Cash and Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 26,845	$ 28,059
Long-term restricted cash	64,438	56,669
Total	91,283	84,728
Reconciliation of cash, cash equivalents, and restricted cash:
Cash and cash equivalents	347,031	380,420
Restricted cash	26,845	28,059
Long-term restricted cash	64,438	56,669
Total cash, cash equivalents, and restricted cash	438,314	465,148	$ 301,697	$ 450,218
Real estate tax and property insurance escrows
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	16,272	17,465
Reconciliation of cash, cash equivalents, and restricted cash:
Restricted cash	16,272	17,465
Replacement reserve escrows
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	9,756	9,465
Reconciliation of cash, cash equivalents, and restricted cash:
Restricted cash	9,756	9,465
Resident deposits
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	93	253
Reconciliation of cash, cash equivalents, and restricted cash:
Restricted cash	93	253
Other
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	724	876
Reconciliation of cash, cash equivalents, and restricted cash:
Restricted cash	724	876
Insurance deposits
Restricted Cash and Cash Equivalents Items [Line Items]
Long-term restricted cash	30,932	21,903
Reconciliation of cash, cash equivalents, and restricted cash:
Long-term restricted cash	30,932	21,903
Debt service reserve
Restricted Cash and Cash Equivalents Items [Line Items]
Long-term restricted cash	18,053	17,784
Reconciliation of cash, cash equivalents, and restricted cash:
Long-term restricted cash	18,053	17,784
CCRCs escrows
Restricted Cash and Cash Equivalents Items [Line Items]
Long-term restricted cash	15,346	15,329
Reconciliation of cash, cash equivalents, and restricted cash:
Long-term restricted cash	15,346	15,329
Letters of credit collateral
Restricted Cash and Cash Equivalents Items [Line Items]
Long-term restricted cash	107	1,653
Reconciliation of cash, cash equivalents, and restricted cash:
Long-term restricted cash	$ 107	$ 1,653