Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended				6 Months Ended				12 Months Ended
	Jul. 31, 2012		Jul. 31, 2011		Jul. 31, 2012		Jul. 31, 2011		Jan. 31, 2012
Numerators
Earnings (loss) from continuing operations attributable to Forest City Enterprises, Inc.	$ (43,885)		$ (9,495)		$ (25,619)		$ 31,844
Dividends on preferred stock	(3,850)		(3,850)		(7,700)		(7,700)		(15,400)
Undistributed earnings allocated to participating securities	0		0		0		(766)
Earnings (loss) from continuing operations attributable to Forest City Enterprises, Inc. common shareholders—Basic	(47,735)		(13,345)		(33,319)		23,378
Undistributed earnings allocated to participating securities	0		0		0		766
Earnings (loss) from continuing operations attributable to Forest City Enterprises, Inc. common shareholders—Diluted	(47,735)		(13,345)		(33,319)		24,144
Net earnings (loss) attributable to Forest City Enterprises, Inc.	(43,717)		9,358		(20,965)		55,701
Undistributed earnings allocated to participating securities	0		(610)		0		(1,523)
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders—Basic	(47,567)		4,898		(28,665)		46,478
Undistributed earnings allocated to participating securities	0		0		0		1,523
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders - Diluted	$ (47,567)		$ 4,898		$ (28,665)		$ 48,001
Denominators
Weighted average shares outstanding - Basic	169,454,672		168,788,754		169,331,996		167,171,093
Effect of stock options and restricted stock	0		0		0		1,036,656
Weighted average shares outstanding - Diluted	169,454,672	[1]	168,788,754	[1]	169,331,996	[1]	168,207,749	[1]
Basic and diluted earnings (loss) per common share
Earnings (loss) from continuing operations attributable to Forest City Enterprises, Inc. common shareholders - Basic	$ (0.28)		$ (0.08)		$ (0.20)		$ 0.14
Earnings (loss) from continuing operations attributable to Forest City Enterprises, Inc. common shareholders - Diluted	$ (0.28)		$ (0.08)		$ (0.20)		$ 0.14
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders - Basic	$ (0.28)		$ 0.03		$ (0.17)		$ 0.28
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders - Diluted	$ (0.28)		$ 0.03		$ (0.17)		$ 0.29

[1] Incremental shares from dilutive options, restricted stock and convertible securities aggregating 52,436,282 and 52,535,035 for the three and six months ended July 31, 2012, respectively, and 39,129,204 for the three months ended July 31, 2011, were not included in the computation of diluted EPS because their effect is anti-dilutive due to loss from continuing operations. Weighted average shares issuable upon the conversion of preferred stock, Class A Common Stock Units, and 2014, 2016 and 2018 Senior Notes aggregating 38,263,518 for the six months ended July 31, 2011 were not included in the computation of diluted EPS because their effect is anti-dilutive under the if-converted method. Weighted-average options, restricted stock and performance shares of 4,474,149 and 4,479,739 for the three and six months ended July 31, 2012, respectively, and 3,611,087 and 3,527,106 for the three and six months ended July 31, 2011, respectively, were not included in the computation of diluted EPS because their effect is anti-dilutive under the treasury stock method.