Consolidated Statements of Capital - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Increase (Decrease) in Partners' Capital [Roll Forward]
Other comprehensive (loss) income - change in value of interest rate swaps, excluding amounts attributable to redeemable noncontrolling interests	$ (1,705)	$ 7,804	$ 3,597
Contributions from noncontrolling interests, excluding amounts attributable to redeemable noncontrolling interests	1,092		6,583
Deconsolidation of VIE		972
Accumulated Other Comprehensive (Loss) Income
Increase (Decrease) in Partners' Capital [Roll Forward]
Other comprehensive (loss) income - change in value of interest rate swaps, excluding amounts attributable to redeemable noncontrolling interests	(1,705)	7,804	3,597
Federal Realty OP LP
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	3,034,015	2,663,148	2,548,747
Net income, excluding amount attributable to redeemable noncontrolling interests	239,964	389,048	264,785
Other comprehensive (loss) income - change in value of interest rate swaps, excluding amounts attributable to redeemable noncontrolling interests	(1,705)	7,804	3,597
Distributions declared to common unit holders	(355,241)	(344,711)	(332,116)
Distributions declared to preferred unit holders	(8,032)	(8,034)	(8,042)
Distributions declared to noncontrolling interests in consolidated partnerships, excluding amounts attributable to redeemable noncontrolling interests	(4,541)	(5,007)	(4,341)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	131,729	306,854	172,753
Exercise of stock options		35
Common units issued under dividend reinvestment plan	1,870	2,104	1,955
Share-based compensation expense, net of forfeitures	15,427	15,018	14,434
Common units withheld for employee taxes	(5,019)	(4,900)	(2,998)
Conversion of preferred units, value		0
Contributions from noncontrolling interests, excluding amounts attributable to redeemable noncontrolling interests	1,092		6,583
Deconsolidation of VIE		972
Adjustment to redeemable noncontrolling interest	(7,400)	12,382	(2,110)
Ending balance	3,042,159	3,034,015	2,663,148
Federal Realty OP LP | downREIT OP units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and redemption of downREIT OP units	0	(698)	(99)
Federal Realty OP LP | Preferred Units
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	154,788	154,963	154,963
Net income, excluding amount attributable to redeemable noncontrolling interests	8,032	8,034	8,042
Distributions declared to preferred unit holders	(8,032)	(8,034)	(8,042)
Conversion of preferred units		(175)
Ending balance	154,788	154,788	154,963
Federal Realty OP LP | Common Units
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	2,793,467	2,427,686	2,314,838
Net income, excluding amount attributable to redeemable noncontrolling interests	228,953	377,457	253,456
Distributions declared to common unit holders	(355,241)	(344,711)	(332,116)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	131,729	306,854	172,753
Exercise of stock options		35
Common units issued under dividend reinvestment plan	1,870	2,104	1,955
Share-based compensation expense, net of forfeitures	15,427	15,018	14,434
Common units withheld for employee taxes	(5,019)	(4,900)	(2,998)
Conversion of preferred units, value		175
Adjustment to redeemable noncontrolling interest	(7,400)	12,382	(2,110)
Ending balance	2,804,669	2,793,467	2,427,686
Federal Realty OP LP | Common Units | downREIT OP units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and redemption of downREIT OP units	883	1,367	7,474
Federal Realty OP LP | Accumulated Other Comprehensive (Loss) Income
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	5,757	(2,047)	(5,644)
Other comprehensive (loss) income - change in value of interest rate swaps, excluding amounts attributable to redeemable noncontrolling interests	(1,705)	7,804	3,597
Ending balance	4,052	5,757	(2,047)
Federal Realty OP LP | Total Partner Capital
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	2,954,012	2,580,602	2,464,157
Net income, excluding amount attributable to redeemable noncontrolling interests	236,985	385,491	261,498
Other comprehensive (loss) income - change in value of interest rate swaps, excluding amounts attributable to redeemable noncontrolling interests	(1,705)	7,804	3,597
Distributions declared to common unit holders	(355,241)	(344,711)	(332,116)
Distributions declared to preferred unit holders	(8,032)	(8,034)	(8,042)
Common units issued as a result of common stock issued by Parent Company, net of issuance costs	131,729	306,854	172,753
Exercise of stock options		35
Common units issued under dividend reinvestment plan	1,870	2,104	1,955
Share-based compensation expense, net of forfeitures	15,427	15,018	14,434
Common units withheld for employee taxes	(5,019)	(4,900)	(2,998)
Adjustment to redeemable noncontrolling interest	(7,400)	12,382	(2,110)
Ending balance	2,963,509	2,954,012	2,580,602
Federal Realty OP LP | Total Partner Capital | downREIT OP units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and redemption of downREIT OP units	883	1,367	7,474
Federal Realty OP LP | Noncontrolling Interests in Consolidated Partnerships
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance	80,003	82,546	84,590
Net income, excluding amount attributable to redeemable noncontrolling interests	2,979	3,557	3,287
Distributions declared to noncontrolling interests in consolidated partnerships, excluding amounts attributable to redeemable noncontrolling interests	(4,541)	(5,007)	(4,341)
Contributions from noncontrolling interests, excluding amounts attributable to redeemable noncontrolling interests	1,092		6,583
Deconsolidation of VIE		972
Ending balance	78,650	80,003	82,546
Federal Realty OP LP | Noncontrolling Interests in Consolidated Partnerships | downREIT OP units
Increase (Decrease) in Partners' Capital [Roll Forward]
Conversion and redemption of downREIT OP units	$ (883)	$ (2,065)	$ (7,573)