Mortgages Loans, Construction Loan, Delayed Draw Term Loan and Interest Rate Swaps (Details) $ in Thousands		2 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Apr. 21, 2022 USD ($) item	Jun. 30, 2022 USD ($) item	Jun. 30, 2022 USD ($) item	Mar. 31, 2021 USD ($)	Jun. 30, 2022 USD ($) building loan item	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Long-Term Debt
Mortgage loans, net of debt issuance costs		$ 106,790	$ 106,790		$ 106,790		$ 169,818
Debt disclosures
Losses on early extinguishment of debt			(464)		$ (464)
Number of mortgage loans repaid | loan					4
Number of buildings mortgaged | building					10
Income tax benefit			$ 585		$ 585
Interest rate swap agreement
Debt disclosures
Number of agreements containing credit risk related contingent features | item		0	0		0
Recognized net gains (losses) (included in other comprehensive loss), before taxes, on interest rate swap agreements				$ 2,963	$ 3,362
Loss expected to be reclassified over next twelve months from accumulated other comprehensive loss to interest expense		$ (432)	$ (432)		(432)
Interest income					$ 449
Interest expense						$ 994
LIBOR | Maximum
Debt disclosures
Variable interest rate margin (as a percent)					1.40%		1.40%
Nonrecourse mortgage loans
Long-Term Debt
Loans, prior to debt issuance costs		81,839	81,839		$ 81,839		$ 145,668
Debt issuance costs, net		(1,155)	(1,155)		(1,155)		(1,745)
Mortgage loans, net of debt issuance costs		$ 80,684	$ 80,684		$ 80,684		$ 143,923
Weighted average interest rate		3.79%	3.79%		3.79%		3.76%
Debt disclosures
Repayment of debt		$ 61,787
Losses on early extinguishment of debt					$ 464
Deferred financing costs		1,155	$ 1,155		1,155		$ 1,745
Nonrecourse mortgage loans | Interest rate swap agreement | Cash flow hedges
Debt disclosures
Gain on hedge		1,227
Income tax benefit					585
Construction loan
Long-Term Debt
Loans, prior to debt issuance costs		26,342	26,342		26,342		26,273
Debt issuance costs, net		(236)	(236)		(236)		(378)
Mortgage loans, net of debt issuance costs		26,106	26,106		26,106		25,895
Debt disclosures
Deferred financing costs		236	236		236		378
Delayed Draw Term Loan Facility
Long-Term Debt
Debt issuance costs, net		(1,436)	(1,436)		(1,436)
Debt disclosures
Maximum borrowing capacity	$ 150,000
Term of debt	5 years
Proceeds from debt		60,000
Deferred financing costs		1,436	1,436		1,436
Interest rate	4.15%
Number of separate draws | item	3
Number of facilities with minimum draw amount | item	2
Minimum draw amount	$ 25,000
Delayed Draw Term Loan Facility | SOFR
Debt disclosures
Variable interest rate margin (as a percent)	1.15%
Existing Credit Facility
Debt disclosures
Maximum borrowing capacity	$ 100,000
New Credit Facility
Debt disclosures
Maximum borrowing capacity	$ 250,000
New Credit Facility | LIBOR
Debt disclosures
Variable interest rate margin (as a percent)	1.20%
3.97%, due September 1, 2027
Long-Term Debt
Loans, prior to debt issuance costs		$ 11,048	$ 11,048		$ 11,048		$ 11,174
Interest rate (as a percent)		3.97%	3.97%		3.97%		3.97%
4.57%, due February 1, 2028
Long-Term Debt
Loans, prior to debt issuance costs		$ 16,908	$ 16,908		$ 16,908		$ 17,145
Interest rate (as a percent)		4.57%	4.57%		4.57%		4.57%
3.60%, due January 2, 2030
Long-Term Debt
Loans, prior to debt issuance costs		$ 6,095	$ 6,095		$ 6,095		$ 6,182
Interest rate (as a percent)		3.60%	3.60%		3.60%		3.60%
3.48% due February 1 2030
Long-Term Debt
Loans, prior to debt issuance costs		$ 14,084	$ 14,084		$ 14,084		$ 14,287
Interest rate (as a percent)		3.48%	3.48%		3.48%		3.48%
3.50%, due July 1, 2030
Long-Term Debt
Loans, prior to debt issuance costs		$ 4,847	$ 4,847		$ 4,847		$ 4,914
Interest rate (as a percent)		3.50%	3.50%		3.50%
4.33%, due August 1, 2030
Long-Term Debt
Loans, prior to debt issuance costs		$ 15,672	$ 15,672		$ 15,672		$ 15,867
Interest rate (as a percent)		4.33%	4.33%		4.33%		4.33%
4.51%, due April 1, 2034
Long-Term Debt
Loans, prior to debt issuance costs		$ 13,185	$ 13,185		$ 13,185		$ 13,356
Interest rate (as a percent)		4.51%	4.51%		4.51%		4.51%
4.39%, due January 2, 2025
Long-Term Debt
Loans, prior to debt issuance costs							$ 17,824
Interest rate (as a percent)		4.39%	4.39%		4.39%		4.39%
4.17%, due May 1, 2026
Long-Term Debt
Loans, prior to debt issuance costs							$ 12,291
Interest rate (as a percent)		4.17%	4.17%		4.17%		4.17%
3.79%, November 17, 2026
Long-Term Debt
Loans, prior to debt issuance costs							$ 23,152
Interest rate (as a percent)		3.79%	3.79%		3.79%		3.79%
4.39%, due August 1, 2027
Long-Term Debt
Loans, prior to debt issuance costs							$ 9,476
Interest rate (as a percent)		4.39%	4.39%		4.39%		4.39%