Segment Information (Details 1) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 31, 2011	Oct. 31, 2010	Oct. 31, 2011	Oct. 31, 2010	Jan. 31, 2011
Reconciliation of EBDT to Net Earnings (Loss) by Segment
EBDT	$ 77,477,000	$ 90,699,000	$ 275,559,000	$ 266,726,000
Depreciation and amortization - Real Estate Groups	(55,415,000)	(60,367,000)	(166,660,000)	(177,733,000)
Amortization of mortgage procurement costs	(3,414,000)	(3,322,000)	(9,036,000)	(8,655,000)
Deferred taxes - Real Estate Groups	3,328,000	(26,960,000)	6,720,000	(87,586,000)
Straight-line rent adjustment	3,268,000	2,170,000	2,424,000	9,079,000
Preference payment	(585,000)	(585,000)	(1,756,000)	(1,756,000)
Gain (loss) on disposition of partial interests in rental properties, net of tax		(1,145,000)		124,201,000
Net gain (loss) on disposition of partial interests in rental properties and other investment	5,849,000	(2,257,000)	15,410,000	257,990,000
Gain on disposition of unconsolidated entities			12,567,000
Gain on disposition of unconsolidated entities, net of tax		5,299,000		4,792,000
Impairment of real estate	(10,707,000)	(5,703,000)	(15,777,000)	(6,803,000)
Impairment of unconsolidated entities	(41,289,000)	(21,564,000)	(41,289,000)	(36,745,000)
Impairment of real estate, net of tax		(2,557,000)		(3,229,000)
Impairment of unconsolidated entities, net of tax		(13,201,000)		(22,495,000)
Discontinued operations:
Straight-line rent adjustment			571,000
Straight-line rent adjustment, net of tax		497,000		1,168,000
Gain (loss) on disposition of rental properties			39,937,000
Gain (loss) on disposition of rental properties, net of tax		(758,000)		341,000
Discontinued Operations Impairment of Real Estate		(20,931,000)		(48,731,000)
Income tax expense:
Deferred income taxes	3,328,000		(7,838,000)
Current income taxes attributable to above dispositions	(10,000)		(41,971,000)
Net earnings (loss) attributable to Forest City Enterprises, Inc.	(38,025,000)	(46,791,000)	17,676,000	60,493,000
Preferred dividends	(3,850,000)	(3,850,000)	(11,550,000)	(7,957,000)	(11,807,000)
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders	(41,875,000)	(50,641,000)	6,126,000	52,536,000
Real Estate Groups [Member]
Reconciliation of EBDT to Net Earnings (Loss) by Segment
Depreciation and amortization - Real Estate Groups	(71,304,000)	(70,977,000)	(208,032,000)	(205,944,000)
Amortization of mortgage procurement costs	(4,052,000)	(3,745,000)	(10,766,000)	(9,959,000)
Deferred taxes - Real Estate Groups		(28,570,000)		(44,852,000)
Discontinued operations:
Depreciation and amortization - Real Estate Groups			(1,030,000)
Depreciation and amortization - Real Estate Groups, net of tax		(1,943,000)		(6,719,000)
Amortization of mortgage procurement costs - Real Estate Groups			(333,000)
Amortization of mortgage procurement costs - Real Estate Groups, net of tax		(284,000)		(765,000)
Deferred taxes - Real Estate Groups		(760,000)		(1,364,000)
Commercial Group [Member]
Reconciliation of EBDT to Net Earnings (Loss) by Segment
EBDT	73,677,000	73,040,000	266,453,000	206,141,000
Depreciation and amortization - Real Estate Groups	(41,675,000)	(44,659,000)	(124,904,000)	(135,909,000)
Straight-line rent adjustment	3,038,000	2,208,000	2,069,000	8,349,000
Preference payment	(585,000)	(585,000)	(1,756,000)	(1,756,000)
Gain (loss) on disposition of partial interests in rental properties, net of tax		(1,497,000)		106,118,000
Net gain (loss) on disposition of partial interests in rental properties and other investment	5,849,000		15,410,000
Gain on disposition of unconsolidated entities, net of tax		3,943,000		3,436,000
Impairment of real estate	(10,257,000)		(13,692,000)
Impairment of unconsolidated entities	(39,189,000)		(39,189,000)
Impairment of real estate, net of tax		(2,213,000)		(2,213,000)
Impairment of unconsolidated entities, net of tax		(1,674,000)		(9,115,000)
Discontinued operations:
Straight-line rent adjustment			571,000
Straight-line rent adjustment, net of tax		497,000		1,168,000
Gain (loss) on disposition of rental properties			39,937,000
Gain (loss) on disposition of rental properties, net of tax		(758,000)		(758,000)
Discontinued Operations Impairment of Real Estate		(20,931,000)		(48,731,000)
Income tax expense:
Net earnings (loss) attributable to Forest City Enterprises, Inc.	(20,868,000)	(7,922,000)	111,123,000	80,671,000
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders	(20,868,000)	(7,922,000)	111,123,000	80,671,000
Commercial Group [Member] | Real Estate Groups [Member]
Reconciliation of EBDT to Net Earnings (Loss) by Segment
Depreciation and amortization - Real Estate Groups	(50,402,000)	(50,678,000)	(149,476,000)	(150,006,000)
Amortization of mortgage procurement costs	(2,999,000)	(2,982,000)	(7,841,000)	(7,889,000)
Deferred taxes - Real Estate Groups		(3,305,000)		(16,274,000)
Discontinued operations:
Depreciation and amortization - Real Estate Groups			(1,030,000)
Depreciation and amortization - Real Estate Groups, net of tax		(1,943,000)		(6,083,000)
Amortization of mortgage procurement costs - Real Estate Groups			(333,000)
Amortization of mortgage procurement costs - Real Estate Groups, net of tax		(284,000)		(752,000)
Deferred taxes - Real Estate Groups		(760,000)		(964,000)
Residential Group [Member]
Reconciliation of EBDT to Net Earnings (Loss) by Segment
EBDT	25,956,000	34,678,000	72,713,000	87,457,000
Depreciation and amortization - Real Estate Groups	(13,276,000)	(15,163,000)	(40,469,000)	(40,195,000)
Straight-line rent adjustment	230,000	(37,000)	355,000	735,000
Gain (loss) on disposition of partial interests in rental properties, net of tax		352,000		18,083,000
Gain on disposition of unconsolidated entities			12,567,000
Gain on disposition of unconsolidated entities, net of tax		1,356,000		1,356,000
Impairment of real estate			(235,000)
Discontinued operations:
Gain (loss) on disposition of rental properties, net of tax				1,099,000
Income tax expense:
Net earnings (loss) attributable to Forest City Enterprises, Inc.	4,330,000	10,652,000	24,317,000	38,743,000
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders	4,330,000	10,652,000	24,317,000	38,743,000
Residential Group [Member] | Real Estate Groups [Member]
Reconciliation of EBDT to Net Earnings (Loss) by Segment
Depreciation and amortization - Real Estate Groups	(20,861,000)	(20,251,000)	(58,362,000)	(55,736,000)
Amortization of mortgage procurement costs	(995,000)	(716,000)	(2,721,000)	(1,859,000)
Deferred taxes - Real Estate Groups		(4,730,000)		(11,343,000)
Discontinued operations:
Depreciation and amortization - Real Estate Groups, net of tax				(636,000)
Amortization of mortgage procurement costs - Real Estate Groups, net of tax				(13,000)
Deferred taxes - Real Estate Groups				(400,000)
Land Development Group [Member]
Reconciliation of EBDT to Net Earnings (Loss) by Segment
EBDT	3,131,000	441,000	4,023,000	1,007,000
Depreciation and amortization - Real Estate Groups	(60,000)	(65,000)	(174,000)	(264,000)
Straight-line rent adjustment		(1,000)		(5,000)
Impairment of real estate	(450,000)		(1,850,000)
Impairment of unconsolidated entities	(2,100,000)		(2,100,000)
Impairment of real estate, net of tax		(344,000)		(1,016,000)
Impairment of unconsolidated entities, net of tax		(11,527,000)		(13,380,000)
Income tax expense:
Net earnings (loss) attributable to Forest City Enterprises, Inc.	482,000	(12,133,000)	(325,000)	(14,634,000)
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders	482,000	(12,133,000)	(325,000)	(14,634,000)
Land Development Group [Member] | Real Estate Groups [Member]
Reconciliation of EBDT to Net Earnings (Loss) by Segment
Depreciation and amortization - Real Estate Groups	(41,000)	(48,000)	(194,000)	(202,000)
Amortization of mortgage procurement costs	(58,000)	(47,000)	(204,000)	(211,000)
Deferred taxes - Real Estate Groups		(607,000)		(827,000)
The Nets [Member]
Reconciliation of EBDT to Net Earnings (Loss) by Segment
EBDT	(11,283,000)	(598,000)	(14,969,000)	10,774,000
Income tax expense:
Net earnings (loss) attributable to Forest City Enterprises, Inc.	(11,283,000)	(598,000)	(14,969,000)	10,774,000
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders	(11,283,000)	(598,000)	(14,969,000)	10,774,000
Corporate Activities [Member]
Reconciliation of EBDT to Net Earnings (Loss) by Segment
EBDT	(14,004,000)	(16,862,000)	(52,661,000)	(38,653,000)
Depreciation and amortization - Real Estate Groups	(404,000)	(480,000)	(1,113,000)	(1,365,000)
Income tax expense:
Deferred income taxes	3,328,000		(7,838,000)
Current income taxes attributable to above dispositions	(10,000)		(41,971,000)
Net earnings (loss) attributable to Forest City Enterprises, Inc.	(10,686,000)	(36,790,000)	(102,470,000)	(55,061,000)
Preferred dividends	(3,850,000)	(3,850,000)	(11,550,000)	(7,957,000)
Net earnings (loss) attributable to Forest City Enterprises, Inc. common shareholders	(14,536,000)	(40,640,000)	(114,020,000)	(63,018,000)
Corporate Activities [Member] | Real Estate Groups [Member]
Reconciliation of EBDT to Net Earnings (Loss) by Segment
Deferred taxes - Real Estate Groups		$ (19,928,000)		$ (16,408,000)