Fair Value Measurements (Details)	Sep. 30, 2022 USD ($) item	Dec. 31, 2021 USD ($) item
Fair value measurements
Number of interest rate swaps | item	2
Notional Amount	$ 100,000,000
Mortgage loans receivable, net of loan loss reserve	383,006,000	$ 344,442,000
Notes receivable, net of loan loss reserve	58,424,000	28,337,000
Term loans, net of debt issue cost	793,761,000	722,719,000
Senior unsecured notes, net of debt issue costs	$ 543,287,000	$ 512,456,000
Level 3 | Senior Unsecured Notes maturing before 2030 | Discount Rate
Fair value measurements
Future cash outflows discount rate (as a percent) | item	0.065	0.0300
Level 3 | Senior Unsecured Notes maturing 2030 and after | Discount Rate
Fair value measurements
Future cash outflows discount rate (as a percent) | item	0.070	0.0325
Level 3 | Mortgage Loans Receivable | Discount Rate
Fair value measurements
Future cash inflows discount rate (as a percent)	0.092	0.095
Level 3 | Notes Receivable | Discount Rate
Fair value measurements
Future cash inflows discount rate (as a percent) | item	0.066	0.056
Carrying Value
Fair value measurements
Mortgage loans receivable, net of loan loss reserve	$ 383,006,000	$ 344,442,000
Revolving line of credit	151,000,000	110,900,000
Term loans, net of debt issue cost	99,474,000	99,363,000
Senior unsecured notes, net of debt issue costs	543,287,000	512,456,000
Carrying Value | Financing Receivable
Fair value measurements
Notes receivable, net of loan loss reserve	75,507,000
Carrying Value | Notes Receivable
Fair value measurements
Notes receivable, net of loan loss reserve	58,424,000	28,337,000
Fair Value
Fair value measurements
Revolving line of credit	151,000,000	110,900,000
Term loans, net of debt issue cost	100,000,000	100,000,000
Fair Value | Financing Receivable
Fair value measurements
Notes receivable, net of loan loss reserve	75,507,000
Fair Value | Level 3
Fair value measurements
Mortgage loans receivable, net of loan loss reserve	454,185,000	405,162,000
Senior unsecured notes, net of debt issue costs	496,955,000	540,045,000
Fair Value | Level 3 | Notes Receivable
Fair value measurements
Notes receivable, net of loan loss reserve	$ 62,741,000	$ 28,653,000