Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Jan. 31, 2012	Jan. 31, 2011	Jan. 31, 2010
Numerators
Earnings (loss) from continuing operations attributable to Forest City Enterprises, Inc.	$ (109,818)	$ 79,940	$ (14,208)
Preferred dividends	(15,400)	(11,807)
Undistributed earnings allocated to participating securities		(2,183)
Earnings (loss) from continuing operations attributable to Forest City Enterprises, Inc. common shareholders - Basic	(125,218)	65,950	(14,208)
Undistributed earnings allocated to participating securities		2,183
Interest on convertible debt		4,438
Preferred distribution on Class A Common Units		1,433
Earnings (loss) from continuing operations attributable to Forest City Enterprises, Inc. common shareholders - Diluted	(125,218)	74,004	(14,208)
Net earnings (loss) attributable to Forest City Enterprises, Inc.	(86,486)	58,048	(26,978)
Undistributed earnings allocated to participating securities		(1,501)
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders - Basic	(101,886)	44,740	(26,978)
Undistributed earnings allocated to participating securities		1,501
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders - Diluted	$ (101,886)	$ 52,112	$ (26,978)
Denominators
Weighted average shares outstanding - Basic	168,170,650	155,485,243	139,825,349
Effect of stock options and restricted stock		550,730
Effect of convertible debt		13,755,158
Effect of convertible Class A Common Units		3,646,755
Weighted average shares outstanding - Diluted	168,170,650	173,437,886	139,825,349
Basic and diluted earnings (loss) per common share
Earnings (loss) from continuing operations attributable to Forest City Enterprises, Inc. common shareholders	$ (0.74)	$ 0.42	$ (0.10)
Earnings (loss) from continuing operations attributable to Forest City Enterprises, Inc. common shareholders - Diluted	$ (0.74)	$ 0.43	$ (0.10)
Basic net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders per common share	$ (0.61)	$ 0.29	$ (0.19)
Diluted net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders per common share	$ (0.61)	$ 0.30	$ (0.19)