Consolidated Statements of Capital - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Increase (Decrease) in Partners' Capital [Roll Forward]
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	$ 57,575	$ 157,000	$ 175,091	$ 272,668
Other comprehensive income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	1,277	2,534	1,016	8,131
Contributions from noncontrolling interests	165		1,092
Deconsolidation of VIE		972		972
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Partners' Capital [Roll Forward]
Other comprehensive income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	1,277	2,534	1,016	8,131
Federal Realty OP LP
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	2,980,431	2,876,427	3,034,015	2,663,148
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	57,575	157,000	175,091	272,668
Other comprehensive income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	1,277	2,534	1,016	8,131
Distributions declared to common unit holders	(88,958)	(87,694)	(265,022)	(256,867)
Distributions declared to preferred unit holders	(2,008)	(2,008)	(6,024)	(6,026)
Distributions declared to noncontrolling interests in consolidated partnerships, excluding amounts attributable to redeemable noncontrolling interests	(1,081)	(1,441)	(3,283)	(4,066)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	9,703	32,892	15,895	292,344
Exercise of stock options		35		35
Common units issued under dividend reinvestment plan	475	573	1,380	1,584
Share-based compensation expense, net of forfeitures	3,738	3,579	11,868	11,258
Common units withheld for employee taxes	(268)	(248)	(4,979)	(4,886)
Conversion of preferred units				0
Contributions from noncontrolling interests	165		1,092
Deconsolidation of VIE		972		972
Adjustment to redeemable noncontrolling interests		(741)		3,585
Ending balance	2,961,049	2,981,880	2,961,049	2,981,880
Federal Realty OP LP | Preferred Units
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	154,788	154,788	154,788	154,963
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	2,008	2,008	6,024	6,026
Distributions declared to preferred unit holders	(2,008)	(2,008)	(6,024)	(6,026)
Conversion of preferred units				(175)
Ending balance	154,788	154,788	154,788	154,788
Federal Realty OP LP | Common Units
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	2,740,405	2,637,545	2,793,467	2,427,686
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	55,040	154,130	166,858	263,772
Distributions declared to common unit holders	(88,958)	(87,694)	(265,022)	(256,867)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	9,703	32,892	15,895	292,344
Exercise of stock options		35		35
Common units issued under dividend reinvestment plan	475	573	1,380	1,584
Share-based compensation expense, net of forfeitures	3,738	3,579	11,868	11,258
Common units withheld for employee taxes	(268)	(248)	(4,979)	(4,886)
Conversion of preferred units				175
Adjustment to redeemable noncontrolling interests		(741)		3,585
Ending balance	2,720,350	2,740,071	2,720,350	2,740,071
Federal Realty OP LP | Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	5,496	3,550	5,757	(2,047)
Other comprehensive income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	1,277	2,534	1,016	8,131
Ending balance	6,773	6,084	6,773	6,084
Federal Realty OP LP | Total Partner Capital
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	2,900,689	2,795,883	2,954,012	2,580,602
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	57,048	156,138	172,882	269,798
Other comprehensive income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	1,277	2,534	1,016	8,131
Distributions declared to common unit holders	(88,958)	(87,694)	(265,022)	(256,867)
Distributions declared to preferred unit holders	(2,008)	(2,008)	(6,024)	(6,026)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	9,703	32,892	15,895	292,344
Exercise of stock options		35		35
Common units issued under dividend reinvestment plan	475	573	1,380	1,584
Share-based compensation expense, net of forfeitures	3,738	3,579	11,868	11,258
Common units withheld for employee taxes	(268)	(248)	(4,979)	(4,886)
Adjustment to redeemable noncontrolling interests		(741)		3,585
Ending balance	2,881,911	2,900,943	2,881,911	2,900,943
Federal Realty OP LP | Noncontrolling Interests in Consolidated Partnerships
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	79,742	80,544	80,003	82,546
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	527	862	2,209	2,870
Distributions declared to noncontrolling interests in consolidated partnerships, excluding amounts attributable to redeemable noncontrolling interests	(1,081)	(1,441)	(3,283)	(4,066)
Contributions from noncontrolling interests	165		1,092
Deconsolidation of VIE		972		972
Ending balance	79,138	$ 80,937	79,138	80,937
Federal Realty OP LP | downREIT OP units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion of downREIT OP units	0		0	0
Federal Realty OP LP | downREIT OP units | Common Units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion of downREIT OP units	215		883	1,385
Federal Realty OP LP | downREIT OP units | Total Partner Capital
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion of downREIT OP units	215		883	1,385
Federal Realty OP LP | downREIT OP units | Noncontrolling Interests in Consolidated Partnerships
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion of downREIT OP units	$ (215)		$ (883)	$ (1,385)