Real Estate (Rental Income) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2021	Dec. 31, 2020
Lease Income [Abstract]
Rental income from operating leases	$ 200,287,000	$ 188,840,000	$ 596,099,000	$ 558,942,000
Earned income from direct financing leases	140,000	148,000	427,000	449,000
Percentage rent	336,000	235,000	1,390,000	1,231,000
Rental Revenues	200,763,000	189,223,000	597,916,000	560,622,000
Real estate expense reimbursement from tenants	4,093,000	3,879,000	12,996,000	12,779,000
Rental income	204,856,000	193,102,000	610,912,000	573,401,000
Rental income accrued during period	493,000	655,000	1,496,000	3,298,000
Repayments of deferred rent	$ 476,000	$ 3,458,000	$ 2,648,000	$ 11,520,000
Originally rent due					$ 4,722,000	$ 51,723,000