Accounting Policies (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Apr. 30, 2012	Apr. 30, 2011
Prior period adjustment and financial statement revision [Abstract]
Operating expenses	$ 166,851	$ 160,689
Deferred income tax expense (benefit)	8,444	116
Earnings (loss) from continuing operations	18,362	40,757
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders	18,902	42,493
Basic earnings (loss) per common share from continuing operations attributable to Forest City Enterprises, Inc. common shareholders	$ 0.08	$ 0.22
Diluted earnings per common share from continuing operations attributable to Forest City Enterprises, Inc. common shareholders	$ 0.08	$ 0.21
Basic net earnings (loss) per common share attributable to Forest City Enterprises, Inc. common shareholders	$ 0.11	$ 0.25
Diluted net earnings (loss) per common share attributable to Forest City Enterprises, Inc. common shareholders	$ 0.11	$ 0.23
Previously reported [Member]
Prior period adjustment and financial statement revision [Abstract]
Operating expenses		158,689
Deferred income tax expense (benefit)		892
Earnings (loss) from continuing operations		41,981
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders		43,717
Basic earnings (loss) per common share from continuing operations attributable to Forest City Enterprises, Inc. common shareholders		$ 0.23
Diluted earnings per common share from continuing operations attributable to Forest City Enterprises, Inc. common shareholders		$ 0.21
Basic net earnings (loss) per common share attributable to Forest City Enterprises, Inc. common shareholders		$ 0.26
Diluted net earnings (loss) per common share attributable to Forest City Enterprises, Inc. common shareholders		$ 0.24
Adjustment [Member]
Prior period adjustment and financial statement revision [Abstract]
Operating expenses		2,000
Deferred income tax expense (benefit)		(776)
Earnings (loss) from continuing operations		(1,224)
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders		$ (1,224)
Basic earnings (loss) per common share from continuing operations attributable to Forest City Enterprises, Inc. common shareholders		$ (0.01)
Basic net earnings (loss) per common share attributable to Forest City Enterprises, Inc. common shareholders		$ (0.01)
Diluted net earnings (loss) per common share attributable to Forest City Enterprises, Inc. common shareholders		$ (0.01)