Indebtedness - Summary Information Concerning Indebtedness (Detail) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Outstanding Principal	$ 2,489,379,000	$ 2,650,743,000
Unamortized Debt Issuance Costs	(16,123,000)	(16,993,000)
Unamortized Loan (Discount)/Premiums	68,832,000	71,586,000
Carrying Amount	$ 2,542,088,000	$ 2,705,336,000
Weighted Average Rate	3.40%	3.20%
Weighted Average Maturity (in years)	5 years 4 months 24 days	5 years 7 months 6 days
Unsecured revolver
Debt Instrument [Line Items]
Outstanding Principal	$ 117,503,000	$ 277,003,000
Unamortized Debt Issuance Costs	(2,770,000)	(2,894,000)
Unamortized Loan (Discount)/Premiums	0	0
Carrying Amount	$ 114,733,000	$ 274,109,000
Weighted Average Rate	1.70%	1.50%
Weighted Average Maturity (in years)	3 years 9 months 18 days	4 years 1 month 6 days
Credit facility borrowing capacity	$ 500,000,000	$ 500,000,000
Unsecured term loans
Debt Instrument [Line Items]
Outstanding Principal	500,000,000	500,000,000
Unamortized Debt Issuance Costs	(1,897,000)	(2,049,000)
Unamortized Loan (Discount)/Premiums	0	0
Carrying Amount	$ 498,103,000	$ 497,951,000
Weighted Average Rate	1.60%	1.40%
Weighted Average Maturity (in years)	2 years 10 months 24 days	3 years 2 months 12 days
Secured credit facilities
Debt Instrument [Line Items]
Outstanding Principal	$ 635,128,000	$ 635,128,000
Unamortized Debt Issuance Costs	(2,660,000)	(2,840,000)
Unamortized Loan (Discount)/Premiums	31,178,000	32,330,000
Carrying Amount	$ 663,646,000	$ 664,618,000
Weighted Average Rate	4.00%	4.00%
Weighted Average Maturity (in years)	6 years 8 months 12 days	6 years 10 months 24 days
Mortgages
Debt Instrument [Line Items]
Outstanding Principal	$ 1,236,748,000	$ 1,238,612,000
Unamortized Debt Issuance Costs	(8,796,000)	(9,210,000)
Unamortized Loan (Discount)/Premiums	37,654,000	39,256,000
Carrying Amount	$ 1,265,606,000	$ 1,268,658,000
Weighted Average Rate	3.90%	3.90%
Weighted Average Maturity (in years)	5 years 10 months 24 days	6 years 2 months 12 days

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount, after accumulated amortization, of debt discount (premium).

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Weighted average interest rate of debt outstanding.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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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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