Earnings Per Share And Unit (Details) - shares	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Jan. 11, 2024
Weighted average unvested shares outstanding	300,000	300,000	300,000	300,000
Federal Realty OP LP
Weighted average unvested units outstanding	300,000	300,000	300,000	300,000
3.25% notes | Exchangeable senior notes
Interest rate	3.25%	3.25%	3.25%	3.25%		3.25%
3.25% notes | Exchangeable senior notes | Federal Realty OP LP
Interest rate	3.25%	3.25%	3.25%	3.25%
5.417% Series 1 Cumulative Convertible Preferred shares
Preferred shares, percentage	5.417%	5.417%	5.417%	5.417%	5.417%
5.417% Series 1 Cumulative Convertible Preferred Units
Preferred units, percentage	5.417%	5.417%	5.417%	5.417%
Stock Options
Anti-dilutive issuable shares	3,019	1,190	1,190	1,190
Stock Options | Federal Realty OP LP
Anti-dilutive issuable units	3,019	1,190	1,190	1,190
Forward Sales Contracts
Anti-dilutive issuable shares		700,000	500,000	700,000
Forward Sales Contracts | Federal Realty OP LP
Anti-dilutive issuable units		700,000	500,000	700,000