Shareholders' Equity - Reconciliation of Changes in Parent Company's Total Shareholders' Equity (Detail) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Beginning Balance	$ 3,520,361	$ 3,474,695	$ 3,378,999	$ 2,692,999	$ 2,549,490	$ 2,378,098	$ 3,378,999	$ 2,378,098
Net proceeds from issuance of common stock	80,219	7,865	92,771	478,331	148,325	180,529
Exercise of stock options			173
Earned portion of non-vested stock	1,822	1,743	1,661	1,683	1,467	1,453
Stock dividend						0
Carrying value less than redemption value on redeemed noncontrolling interest	(191)	(2)		(15)	(13)	(4)
Adjustment to redemption value on noncontrolling redeemable Operating Partnership Units	(1,958)	27,930	10,924	(3,570)	(7,142)	(2,358)
Net income attributable to common shareholders	98,505	92,264	73,575	70,274	57,516	47,383	264,344	175,172
Amortization of terminated hedge included in AOCL	229	229	229	229	229	229
Dividends	(91,135)	(84,363)	(83,637)	(57,953)	(56,873)	(55,840)
Ending Balance	3,607,852	3,520,361	3,474,695	3,181,978	2,692,999	2,549,490	3,607,852	3,181,978
Common Stock Shares [Member]
Beginning Balance	844	843	836	781	765	495	836	495
Net proceeds from issuance of common stock	6	1	7	39	16	18
Exercise of stock options			0
Earned portion of non-vested stock	0	0	0	0	0	0
Stock dividend						252
Carrying value less than redemption value on redeemed noncontrolling interest	0	0		0	0	0
Adjustment to redemption value on noncontrolling redeemable Operating Partnership Units	0	0	0	0	0	0
Net income attributable to common shareholders	0	0	0	0	0	0
Amortization of terminated hedge included in AOCL	0	0	0	0	0	0
Dividends	0	0	0	0	0	0
Ending Balance	850	844	843	820	781	765	850	820
Additional Paid-in Capital [Member]
Beginning Balance	3,801,203	3,791,598	3,697,000	3,002,782	2,853,019	2,671,311	3,697,000	2,671,311
Net proceeds from issuance of common stock	80,213	7,864	92,764	478,292	148,309	180,511
Exercise of stock options			173
Earned portion of non-vested stock	1,822	1,743	1,661	1,683	1,467	1,453
Stock dividend						(252)
Carrying value less than redemption value on redeemed noncontrolling interest	(191)	(2)		(15)	(13)	(4)
Adjustment to redemption value on noncontrolling redeemable Operating Partnership Units	0	0	0	0	0	0
Net income attributable to common shareholders	0	0	0	0	0	0
Amortization of terminated hedge included in AOCL	0	0	0	0	0	0
Dividends	0	0	0	0	0	0
Ending Balance	3,883,047	3,801,203	3,791,598	3,482,742	3,002,782	2,853,019	3,883,047	3,482,742
Dividends in Excess of Net Income [Member]
Beginning Balance	(278,020)	(313,851)	(314,713)	(305,981)	(299,482)	(288,667)	(314,713)	(288,667)
Net proceeds from issuance of common stock	0	0	0	0	0	0
Exercise of stock options			0
Earned portion of non-vested stock	0	0	0	0	0	0
Stock dividend						0
Carrying value less than redemption value on redeemed noncontrolling interest	0	0		0	0	0
Adjustment to redemption value on noncontrolling redeemable Operating Partnership Units	(1,958)	27,930	10,924	(3,570)	(7,142)	(2,358)
Net income attributable to common shareholders	98,505	92,264	73,575	70,274	57,516	47,383
Amortization of terminated hedge included in AOCL	0	0	0	0	0	0
Dividends	(91,135)	(84,363)	(83,637)	(57,953)	(56,873)	(55,840)
Ending Balance	(272,608)	(278,020)	(313,851)	(297,230)	(305,981)	(299,482)	(272,608)	(297,230)
Accumulated Other Comprehensive Income (Loss) [Member]
Beginning Balance	(3,666)	(3,895)	(4,124)	(4,583)	(4,812)	(5,041)	(4,124)	(5,041)
Net proceeds from issuance of common stock	0	0	0	0	0	0
Exercise of stock options			0
Earned portion of non-vested stock	0	0	0	0	0	0
Stock dividend						0
Carrying value less than redemption value on redeemed noncontrolling interest	0	0		0	0	0
Adjustment to redemption value on noncontrolling redeemable Operating Partnership Units	0	0	0	0	0	0
Net income attributable to common shareholders	0	0	0	0	0	0
Amortization of terminated hedge included in AOCL	229	229	229	229	229	229
Dividends	0	0	0	0	0	0
Ending Balance	$ (3,437)	$ (3,666)	$ (3,895)	$ (4,354)	$ (4,583)	$ (4,812)	$ (3,437)	$ (4,354)