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Stockholders' Equity - Additional Information (Detail) - USD ($)			1 Months Ended				3 Months Ended						9 Months Ended		12 Months Ended
	Mar. 02, 2026	Mar. 01, 2025	Feb. 28, 2026	Dec. 31, 2025	Jul. 31, 2024	Feb. 28, 2023	Sep. 30, 2026	Jun. 30, 2026	Dec. 31, 2025	Sep. 30, 2025	Dec. 31, 2024	Jun. 30, 2024	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Shareholders Equity [Line Items]
Common stock, shares outstanding				59,815,921			67,123,296		59,815,921				67,123,296		59,815,921
Proceeds from issuance of common stock, net							$ 128,200,000
Number of shares settled under forward provisions							4,000,000
Payment of regular quarterly dividend													$ 91,000,000	$ 80,800,000
Regular quarterly dividends paid per share													$ 1.455	$ 1.41
Shares issued pursuant to dividend reinvestment, shares													1,397	1,709
Shares issued pursuant to dividend reinvestment, value							$ 11,000			$ 16,000			$ 44,000	$ 48,000
Proceeds from issuance of common stock under the dividend reinvestment plan													44,000	48,000
Stock based compensation expense													$ 4,300,000	$ 5,200,000
Common Stock [Member]
Shareholders Equity [Line Items]
Shares issued pursuant to Offering/Program net, shares							4,000,000			1,150,000			4,000,000	2,300,000
Shares issued pursuant to dividend reinvestment, shares							1,000						1,000	1,000
Follow-on Public Offering [Member]
Shareholders Equity [Line Items]
Proceeds from issuance of common stock, net				$ 113,600,000
Number of shares settled under forward provisions				4,000,000
Follow-on Public Offering [Member] \| February 2026 Forward Offering [Member] \| Common Stock [Member]
Shareholders Equity [Line Items]
Shares issued pursuant to Offering/Program net, shares			4,000,000
Follow-on Public Offering [Member] \| July 2024 Forward Offering [Member] \| Common Stock [Member]
Shareholders Equity [Line Items]
Shares issued pursuant to Offering/Program net, shares					4,000,000
ATM Program [Member]
Shareholders Equity [Line Items]
Proceeds from issuance of common stock, net							$ 36,400,000	$ 36,370,000	$ 12,242,000	$ 27,548,000	$ 19,922,000	$ 10,899,000	$ 96,082,000	$ 10,899,000
Number of shares settled under forward provisions							1,100,000	1,100,000	441,850	1,018,695	650,000	406,727	3,210,545	406,727	342,696
ATM Program [Member] \| Common Stock [Member]
Shareholders Equity [Line Items]
Shares issued pursuant to Offering/Program net, shares							1,100,000						3,211,000	407,000
ATM Program [Member] \| Maximum [Member]
Shareholders Equity [Line Items]
Aggregate sales price						$ 350
ATM Direct Issuances [Member] \| Common Stock [Member]
Shareholders Equity [Line Items]
Shares issued pursuant to Offering/Program net, shares													0	0
At The Market Forward Agreements [Member]
Shareholders Equity [Line Items]
Proceeds from issuance of common stock, net							$ 10,900,000						$ 10,900,000
Number of shares settled under forward provisions										0				406,727
Amended and Restated 2004 Omnibus Incentive Compensation Plan [Member] \| Restricted Stock Units [Member]
Shareholders Equity [Line Items]
Granted, Number of RSUs Outstanding	276,225	293,605