Earnings Per Share (Schedule Of Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Earnings Per Share Narrative [Line Items]
Net income	$ 247,217	$ 395,661	$ 269,081
Less: Preferred share dividends	(8,032)	(8,034)	(8,042)
Less: Income from operations attributable to noncontrolling interests	(10,232)	(10,170)	(7,583)
Less: Earnings allocated to unvested shares	(1,286)	(1,328)	(1,211)
Net income available for common shareholders, basic	227,667	376,129	252,245
Add: Income attributable to downREIT operating partnership units	0	2,810	0
Net income available for common shareholders, diluted	$ 227,667	$ 378,939	$ 252,245
Weighted average common shares outstanding—basic	81,313	79,854	77,336
Open forward contracts for share issuances	0	0	32
DownREIT operating partnership units	0	654	0
Weighted average common shares outstanding—diluted	81,313	80,508	77,368
EARNINGS PER COMMON SHARE, BASIC
Net income available for common shareholders	$ 2.80	$ 4.71	$ 3.26
EARNINGS PER COMMON SHARE, DILUTED
Net income available for common shareholders	$ 2.80	$ 4.71	$ 3.26
Federal Realty OP LP
Earnings Per Share Narrative [Line Items]
Net income	$ 247,217	$ 395,661	$ 269,081
Less: Preferred unit distributions	(8,032)	(8,034)	(8,042)
Less: Income from operations attributable to noncontrolling interests	(10,232)	(10,170)	(7,583)
Less: Earnings allocated to unvested units	(1,286)	(1,328)	(1,211)
Net income available for common unit holders, basic	227,667	376,129	252,245
Add: Income attributable to downREIT operating partnership units	0	2,810	0
Net income available for common unit holders, diluted	$ 227,667	$ 378,939	$ 252,245
Weighted average common units outstanding—basic	81,313	79,854	77,336
Common unit issuances relating to open common share forward contracts	0	0	32
DownREIT operating partnership units	0	654	0
Weighted average common units outstanding—diluted	81,313	80,508	77,368
EARNINGS PER COMMON UNIT, BASIC
Net income available for common unit holders	$ 2.80	$ 4.71	$ 3.26
EARNINGS PER COMMON UNIT, DILUTED
Net income available for common unit holders	$ 2.80	$ 4.71	$ 3.26