Stockholders' Equity - Additional Information (Detail) - USD ($)			1 Months Ended		3 Months Ended		6 Months Ended
	Mar. 01, 2023	Mar. 01, 2022	Feb. 28, 2023	Feb. 28, 2021	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Shareholders Equity [Line Items]
Payment of regular quarterly dividend							$ 41,545,000	$ 39,085,000
Regular quarterly dividends paid per share							$ 0.86	$ 0.82
Shares issued pursuant to dividend reinvestment, value					$ 13,000	$ 14,000	$ 28,000	$ 30,000
Stock based compensation expense							$ 2,719,000	$ 2,316,000
February 2023 Forward Offering [Member]
Shareholders Equity [Line Items]
Proceeds from issuance of common stock			$ 112,505,000
Common Stock [Member]
Shareholders Equity [Line Items]
Shares issued pursuant to dividend reinvestment, shares					1,000	1,000	817	996
Shares issued pursuant to dividend reinvestment, value							$ 28,000	$ 30,000
Follow-on Public Offering [Member] | Common Stock [Member] | February 2023 Forward Offering [Member]
Shareholders Equity [Line Items]
Shares issued pursuant to Offering/Program net, shares			3,450,000
Underwriters' Option to Purchase [Member] | Common Stock [Member] | February 2023 Forward Offering [Member]
Shareholders Equity [Line Items]
Shares issued pursuant to Offering/Program net, shares			450,000
2021 ATM Program [Member]
Shareholders Equity [Line Items]
Proceeds from issuance of common stock					$ 31,159,000		$ 114,117,000
Remaining number of shares subject to forward sale agreements					0		0
Number of shares settled under forward provisions					1,007,230		3,721,366
2021 ATM Program [Member] | Common Stock [Member]
Shareholders Equity [Line Items]
Shares issued pursuant to Offering/Program net, shares					0	0	0	0
2021 ATM Program [Member] | Maximum [Member]
Shareholders Equity [Line Items]
Aggregate sales price				$ 250,000,000
ATM Program [Member]
Shareholders Equity [Line Items]
Proceeds from issuance of common stock							$ 114,116,000	$ (83,000)
Number of shares allowed for sale under forward provisions					217,561		217,561
Number of shares settled under forward provisions					0		0
ATM Program [Member] | Common Stock [Member]
Shareholders Equity [Line Items]
Shares issued pursuant to Offering/Program net, shares					1,007,000		3,721,000
Sale of common stock average gross offering price per share					$ 34.97		$ 34.97
ATM Program [Member] | Maximum [Member]
Shareholders Equity [Line Items]
Aggregate sales price			$ 350,000,000
Amended and Restated 2004 Omnibus Incentive Compensation Plan [Member] | Restricted Stock Units [Member]
Shareholders Equity [Line Items]
Granted, Number of RSUs Outstanding	253,075	238,850