Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Mortgage Notes Payable - Summary of Company's Mortgage Notes Payable (Detail) - USD ($) $ in Thousands		6 Months Ended
	Dec. 20, 2017	Jun. 30, 2021	Dec. 31, 2020	Mar. 21, 2018
Debt Instrument [Line Items]
Mortgage notes payable		$ 365,821	$ 366,201
Unamortized loan costs		(4,154)	(4,618)
Mortgage notes payable, net		361,667	361,583
4.18% People's United Bank, Loan [Member]
Debt Instrument [Line Items]
Mortgage notes payable		$ 15,500	15,500
Interest Rate		4.18%
Maturity		Oct. 15, 2024
American International Group, Loan [Member]
Debt Instrument [Line Items]
Mortgage notes payable		$ 233,100	233,100
Interest Rate		4.05%
Maturity		Mar. 01, 2025
Allstate Life Insurance Company, Loan [Member]
Debt Instrument [Line Items]
Mortgage notes payable		$ 36,821	37,201
Interest Rate		4.00%
Maturity		Apr. 01, 2025
3.82 % United States Life Insurance Company, Loan [Member]
Debt Instrument [Line Items]
Mortgage notes payable	$ 39,000	$ 39,000	39,000
Interest Rate	3.82%	3.82%
Maturity	Jan. 01, 2028	Jan. 01, 2028
4.25 % United States Life Insurance Company, Loan [Member]
Debt Instrument [Line Items]
Mortgage notes payable		$ 33,000	33,000	$ 33,000
Interest Rate		4.25%
Maturity		Apr. 01, 2028
3.45% Transamerica Life Insurance Company, Loan One [Member]
Debt Instrument [Line Items]
Mortgage notes payable		$ 5,980	5,980
Interest Rate		3.45%
Maturity		Apr. 01, 2030
3.45% Transamerica Life Insurance Company, Loan Two [Member]
Debt Instrument [Line Items]
Mortgage notes payable		$ 2,420	$ 2,420
Interest Rate		3.45%
Maturity		Apr. 01, 2030