Consolidated Statements of Capital - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Increase (Decrease) in Partners' Capital [Roll Forward]
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	$ 66,993	$ 62,513	$ 313,387	$ 285,031
Other comprehensive (loss) income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	5,014	(680)	11,307	(2,508)
Conversion of and Redemption of downREIT OP units and purchase of noncontrolling interest	(1,800)		(1,800)
Contributions from noncontrolling interests			265
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Partners' Capital [Roll Forward]
Other comprehensive (loss) income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	5,014	(680)	11,307	(2,508)
downREIT OP units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion of and Redemption of downREIT OP units and purchase of noncontrolling interest		(81)	(324)	(7,334)
Federal Realty OP LP
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	3,434,572	3,320,100	3,318,986	3,244,144
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	66,993	62,513	313,387	285,031
Other comprehensive (loss) income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	5,014	(680)	11,307	(2,508)
Distributions declared to common unit holders	(100,164)	(97,474)	(295,957)	(287,282)
Distributions on preferred units	(2,008)	(2,008)	(6,024)	(6,024)
Distributions declared to noncontrolling interests in consolidated partnerships, excluding amounts attributable to redeemable noncontrolling interests	(665)	(1,110)	(2,467)	(3,334)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	(67)	(86)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs			60,321	54,306
Common units issued under dividend reinvestment plan	397	461	1,229	1,368
Share-based compensation expense, net of forfeitures	4,037	3,691	12,364	11,634
Common units repurchased	(65,000)		(65,000)
Common units withheld for employee taxes	(332)	(181)	(5,310)	(4,856)
Conversion of and Redemption of downREIT OP units and purchase of noncontrolling interest	(1,800)		(1,800)
Contributions from noncontrolling interests			265
Purchase of capped calls	(21,712)		(21,712)
Ending balance	3,319,265	3,285,145	3,319,265	3,285,145
Federal Realty OP LP \| Preferred Units
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	154,788	154,788	154,788	154,788
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	2,008	2,008	6,024	6,024
Distributions on preferred units	(2,008)	(2,008)	(6,024)	(6,024)
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	3,201,402	3,091,329	3,091,896	3,012,066
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	64,161	59,641	304,946	275,309
Distributions declared to common unit holders	(100,164)	(97,474)	(295,957)	(287,282)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	(67)	(86)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs			60,321	54,306
Common units issued under dividend reinvestment plan	397	461	1,229	1,368
Share-based compensation expense, net of forfeitures	4,037	3,691	12,364	11,634
Common units repurchased	(65,000)		(65,000)
Common units withheld for employee taxes	(332)	(181)	(5,310)	(4,856)
Conversion of and Redemption of downREIT OP units and purchase of noncontrolling interest	451		451
Purchase of capped calls	(21,712)		(21,712)
Ending balance	3,083,173	3,057,538	3,083,173	3,057,538
Federal Realty OP LP \| Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	8,340	2,912	2,047	4,740
Other comprehensive (loss) income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	5,014	(680)	11,307	(2,508)
Ending balance	13,354	2,232	13,354	2,232
Federal Realty OP LP \| Total Partner Capital
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	3,364,530	3,249,029	3,248,731	3,171,594
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	66,169	61,649	310,970	281,333
Other comprehensive (loss) income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	5,014	(680)	11,307	(2,508)
Distributions declared to common unit holders	(100,164)	(97,474)	(295,957)	(287,282)
Distributions on preferred units	(2,008)	(2,008)	(6,024)	(6,024)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	(67)	(86)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs			60,321	54,306
Common units issued under dividend reinvestment plan	397	461	1,229	1,368
Share-based compensation expense, net of forfeitures	4,037	3,691	12,364	11,634
Common units repurchased	(65,000)		(65,000)
Common units withheld for employee taxes	(332)	(181)	(5,310)	(4,856)
Conversion of and Redemption of downREIT OP units and purchase of noncontrolling interest	451		451
Purchase of capped calls	(21,712)		(21,712)
Ending balance	3,251,315	3,214,558	3,251,315	3,214,558
Federal Realty OP LP \| Noncontrolling Interests in Consolidated Partnerships
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	70,042	71,071	70,255	72,550
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	824	864	2,417	3,698
Distributions declared to noncontrolling interests in consolidated partnerships, excluding amounts attributable to redeemable noncontrolling interests	(665)	(1,110)	(2,467)	(3,334)
Conversion of and Redemption of downREIT OP units and purchase of noncontrolling interest	(2,251)		(2,251)
Contributions from noncontrolling interests			265
Ending balance	$ 67,950	70,587	67,950	70,587
Federal Realty OP LP \| downREIT OP units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and redemption of downREIT OP units		(81)	(324)	(7,334)
Federal Realty OP LP \| downREIT OP units \| Common Units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and redemption of downREIT OP units		157	(55)	(5,007)
Federal Realty OP LP \| downREIT OP units \| Total Partner Capital
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and redemption of downREIT OP units		157	(55)	(5,007)
Federal Realty OP LP \| downREIT OP units \| Noncontrolling Interests in Consolidated Partnerships
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and redemption of downREIT OP units		$ (238)	$ (269)	$ (2,327)

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after income tax of income (loss) including the portion attributable to nonredeemable noncontrolling interest. Excludes the portion attributable to redeemable noncontrolling interest recognized as temporary equity.

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Total contributions made by each class of partners (i.e., general, limited and preferred partners).

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Amount of partners' capital (deficit), including portions attributable to both the parent and noncontrolling interests. Excludes temporary equity and is sometimes called permanent equity.

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