Consolidated Statements of Capital - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Increase (Decrease) in Partners' Capital [Roll Forward]
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	$ 86,498	$ 157,943	$ 246,394	$ 222,518
Other comprehensive (loss) income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	3,265	(684)	6,293	(1,828)
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	3,265	(684)	6,293	(1,828)
downREIT OP units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and Redemption of downREIT OP units		(7,253)	(324)	(7,253)
Federal Realty OP LP
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	3,381,517	3,264,266	3,318,986	3,244,144
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	86,498	157,943	246,394	222,518
Other comprehensive (loss) income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	3,265	(684)	6,293	(1,828)
Distributions declared to common unit holders	(98,167)	(94,933)	(195,793)	(189,808)
Distributions on preferred units	(2,008)	(2,008)	(4,016)	(4,016)
Distributions declared to noncontrolling interests in consolidated partnerships, excluding amounts attributable to redeemable noncontrolling interests	(1,134)	(1,355)	(1,802)	(2,224)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	60,388	(102)	60,388	54,392
Common units issued under dividend reinvestment plan	475	463	832	907
Share-based compensation expense, net of forfeitures	3,790	3,831	8,327	7,943
Common units withheld for employee taxes	(52)	(68)	(4,978)	(4,675)
Contributions from noncontrolling interests			265
Ending balance	3,434,572	3,320,100	3,434,572	3,320,100
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	4,016	4,016
Distributions on preferred units	(2,008)	(2,008)	(4,016)	(4,016)
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	3,151,274	3,033,497	3,091,896	3,012,066
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	83,694	153,908	240,785	215,668
Distributions declared to common unit holders	(98,167)	(94,933)	(195,793)	(189,808)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	60,388	(102)	60,388	54,392
Common units issued under dividend reinvestment plan	475	463	832	907
Share-based compensation expense, net of forfeitures	3,790	3,831	8,327	7,943
Common units withheld for employee taxes	(52)	(68)	(4,978)	(4,675)
Ending balance	3,201,402	3,091,329	3,201,402	3,091,329
Federal Realty OP LP \| Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	5,075	3,596	2,047	4,740
Other comprehensive (loss) income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	3,265	(684)	6,293	(1,828)
Ending balance	8,340	2,912	8,340	2,912
Federal Realty OP LP \| Total Partner Capital
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	3,311,137	3,191,881	3,248,731	3,171,594
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	85,702	155,916	244,801	219,684
Other comprehensive (loss) income - change in fair value of interest rate swaps, excluding portion attributable to redeemable noncontrolling interests	3,265	(684)	6,293	(1,828)
Distributions declared to common unit holders	(98,167)	(94,933)	(195,793)	(189,808)
Distributions on preferred units	(2,008)	(2,008)	(4,016)	(4,016)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	60,388	(102)	60,388	54,392
Common units issued under dividend reinvestment plan	475	463	832	907
Share-based compensation expense, net of forfeitures	3,790	3,831	8,327	7,943
Common units withheld for employee taxes	(52)	(68)	(4,978)	(4,675)
Ending balance	3,364,530	3,249,029	3,364,530	3,249,029
Federal Realty OP LP \| Noncontrolling Interests in Consolidated Partnerships
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	70,380	72,385	70,255	72,550
Net Income, excluding amounts attributable to redeemable noncontrolling Interests	796	2,027	1,593	2,834
Distributions declared to noncontrolling interests in consolidated partnerships, excluding amounts attributable to redeemable noncontrolling interests	(1,134)	(1,355)	(1,802)	(2,224)
Contributions from noncontrolling interests			265
Ending balance	$ 70,042	71,071	70,042	71,071
Federal Realty OP LP \| downREIT OP units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and redemption of downREIT OP units		(7,253)	(324)	(7,253)
Federal Realty OP LP \| downREIT OP units \| Common Units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and redemption of downREIT OP units		(5,267)	(55)	(5,164)
Federal Realty OP LP \| downREIT OP units \| Total Partner Capital
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and redemption of downREIT OP units		(5,267)	(55)	(5,164)
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		$ (1,986)	$ (269)	$ (2,089)

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Contributions from noncontrolling interests

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Distributions declared to noncontrolling interests in consolidated partnerships, excluding amounts attributable to redeemable noncontrolling interests

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Distributions declared to preferred unit holders

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Other Comprehensive Income (loss), net of portion attributable to noncontrolling interest

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Partners capital account employee tax withholdings

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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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Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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Total change in each class of partners' capital accounts during the year due to exchanges and conversions. Partners include general, limited and preferred partners.

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Amount of increase (decrease) in partners' capital account for unit-based payment arrangement issued by partnership. Partner includes, but is not limited to, 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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