Investments - Loans Receivable (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2022 USD ($) loan	Dec. 31, 2021 USD ($)
Scheduled loan receivable maturities
Number of loans receivable | loan	41
Gross carrying amount of loans receivable	$ 334,300
Number of mortgage loans | loan	23
Number of mortgage loans subject to interest rate increases | loan	10
Number of short-term mortgage loans | loan	6
Amortization period of long-term mortgage loans	40 years
Remainder of 2022	$ 26,816
2023	81,700
2024	2,121
2025	1,916
2026	22,248
2027	2,124
Thereafter	200,314
Total principal payments	337,239
Sale-Leaseback Transactions Accounted for as Financing Arrangements
Sale-leaseback transactions accounted for as financing arrangements	316,200	$ 255,500
Remainder of 2022	12,114
2023	24,289
2024	24,436
2025	24,589
2026	24,697
2027	24,812
Thereafter	295,257
Total future scheduled payments	430,194
Components of investments accounted for as direct financing receivables
Minimum lease payments receivable	123,031	159,371
Estimated residual value of leased assets	6,889	8,938
Unearned income	(68,857)	(89,672)
Net investment	61,063	$ 78,637
Future minimum lease payments to be received under the direct financing lease receivables
Remainder of 2022	3,200
2023	6,500
2024	6,500
2025	6,500
2026	6,500
2027	6,500
Thereafter	87,500
Scheduled Principal Payments
Scheduled loan receivable maturities
Remainder of 2022	1,524
2023	3,221
2024	2,121
2025	1,916
2026	1,877
2027	1,576
Thereafter	182,139
Total principal payments	194,374
Balloon Payments
Scheduled loan receivable maturities
Remainder of 2022	25,292
2023	78,479
2026	20,371
2027	548
Thereafter	18,175
Total principal payments	$ 142,865
Minimum
Scheduled loan receivable maturities
Long-term mortgage loans receivable prepayment penalty rate (as a percent)	1.00%
Maximum
Scheduled loan receivable maturities
Long-term mortgage loans receivable prepayment penalty rate (as a percent)	20.00%