Real Estate and Accumulated Depreciation (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jan. 31, 2013
Real Estate and Accumulated Depreciation [Line Items]
Amount of Encumbrance at January 31,2013	$ 5,740,660
Initial Cost to Company, Land	1,749,433
Initial Cost to Company, Buildings and Improvements	6,841,409
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,435,168
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,937,649
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	8,088,361
Gross Amount at Which Carried at Close of January 31, 2013, Total	10,026,010
Accumulated Depreciation at January 31, 2013	1,654,632
Office Buildings and Hotel [Member]
Real Estate and Accumulated Depreciation [Line Items]
Amount of Encumbrance at January 31,2013	1,955,868
Initial Cost to Company, Land	156,525
Initial Cost to Company, Buildings and Improvements	2,090,486
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	703,177
Gross Amount at Which Carried at Close of January 31, 2013, Land	257,746
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	2,692,442
Gross Amount at Which Carried at Close of January 31, 2013, Total	2,950,188
Accumulated Depreciation at January 31, 2013	752,574
Office Buildings and Hotel [Member] | 2 Hanson Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	104,626
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	108,940
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	3,661
Gross Amount at Which Carried at Close of January 31, 2013, Land	0
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	112,601
Gross Amount at Which Carried at Close of January 31, 2013, Total	112,601
Accumulated Depreciation at January 31, 2013	19,159
Date of Construction/Acquisition	2004
Office Buildings and Hotel [Member] | 4930 Oakton [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Skokie, IL
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	670
Initial Cost to Company, Buildings and Improvements	1,842
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	2,554
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,081
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	3,985
Gross Amount at Which Carried at Close of January 31, 2013, Total	5,066
Accumulated Depreciation at January 31, 2013	573
Date of Construction/Acquisition	2006
Office Buildings and Hotel [Member] | Ballston Common Office Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Arlington, VA
Amount of Encumbrance at January 31,2013	44,170
Initial Cost to Company, Land	7,301
Initial Cost to Company, Buildings and Improvements	45,964
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	5,495
Gross Amount at Which Carried at Close of January 31, 2013, Land	7,301
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	51,459
Gross Amount at Which Carried at Close of January 31, 2013, Total	58,760
Accumulated Depreciation at January 31, 2013	9,105
Date of Construction/Acquisition	2005
Office Buildings and Hotel [Member] | Colorado Studios [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Denver, CO
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	899
Initial Cost to Company, Buildings and Improvements	1,085
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	49
Gross Amount at Which Carried at Close of January 31, 2013, Land	948
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	1,085
Gross Amount at Which Carried at Close of January 31, 2013, Total	2,033
Accumulated Depreciation at January 31, 2013	577
Date of Construction/Acquisition	2007
Office Buildings and Hotel [Member] | Commerce Court [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Pittsburgh, PA
Amount of Encumbrance at January 31,2013	24,727
Initial Cost to Company, Land	3,432
Initial Cost to Company, Buildings and Improvements	20,873
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	2,534
Gross Amount at Which Carried at Close of January 31, 2013, Land	3,432
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	23,407
Gross Amount at Which Carried at Close of January 31, 2013, Total	26,839
Accumulated Depreciation at January 31, 2013	6,681
Date of Construction/Acquisition	2007
Office Buildings and Hotel [Member] | Edgeworth Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Richmond, VA
Amount of Encumbrance at January 31,2013	19,207
Initial Cost to Company, Land	942
Initial Cost to Company, Buildings and Improvements	29,353
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	2,033
Gross Amount at Which Carried at Close of January 31, 2013, Land	951
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	31,377
Gross Amount at Which Carried at Close of January 31, 2013, Total	32,328
Accumulated Depreciation at January 31, 2013	3,751
Date of Construction/Acquisition	2006
Office Buildings and Hotel [Member] | Eleven MetroTech Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	61,000
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	41,290
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	8,835
Gross Amount at Which Carried at Close of January 31, 2013, Land	6,270
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	43,855
Gross Amount at Which Carried at Close of January 31, 2013, Total	50,125
Accumulated Depreciation at January 31, 2013	19,742
Date of Construction/Acquisition	1995
Office Buildings and Hotel [Member] | Fifteen MetroTech Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	250,000
Initial Cost to Company, Land	3,762
Initial Cost to Company, Buildings and Improvements	163,414
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	8,488
Gross Amount at Which Carried at Close of January 31, 2013, Land	0
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	175,664
Gross Amount at Which Carried at Close of January 31, 2013, Total	175,664
Accumulated Depreciation at January 31, 2013	32,486
Date of Construction/Acquisition	2003
Office Buildings and Hotel [Member] | Halle Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Cleveland, OH
Amount of Encumbrance at January 31,2013	11,311
Initial Cost to Company, Land	503
Initial Cost to Company, Buildings and Improvements	9,776
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	33,217
Gross Amount at Which Carried at Close of January 31, 2013, Land	4,821
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	38,675
Gross Amount at Which Carried at Close of January 31, 2013, Total	43,496
Accumulated Depreciation at January 31, 2013	36,403
Date of Construction/Acquisition	1986
Office Buildings and Hotel [Member] | Harlem Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Manhattan, NY
Amount of Encumbrance at January 31,2013	31,445
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	31,672
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	8,362
Gross Amount at Which Carried at Close of January 31, 2013, Land	0
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	40,034
Gross Amount at Which Carried at Close of January 31, 2013, Total	40,034
Accumulated Depreciation at January 31, 2013	6,751
Date of Construction/Acquisition	2003
Office Buildings and Hotel [Member] | Higbee Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Cleveland, OH
Amount of Encumbrance at January 31,2013	15,624
Initial Cost to Company, Land	2,452
Initial Cost to Company, Buildings and Improvements	21,261
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	58,727
Gross Amount at Which Carried at Close of January 31, 2013, Land	4,962
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	77,478
Gross Amount at Which Carried at Close of January 31, 2013, Total	82,440
Accumulated Depreciation at January 31, 2013	11,400
Date of Construction/Acquisition	1990
Office Buildings and Hotel [Member] | 4901 Searle (A) [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Skokie, IL
Amount of Encumbrance at January 31,2013	21,305
Initial Cost to Company, Land	837
Initial Cost to Company, Buildings and Improvements	16,227
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	4,491
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,674
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	19,881
Gross Amount at Which Carried at Close of January 31, 2013, Total	21,555
Accumulated Depreciation at January 31, 2013	2,829
Date of Construction/Acquisition	2006
Office Buildings and Hotel [Member] | 8025 Lamon (P) [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Skokie, IL
Amount of Encumbrance at January 31,2013	15,400
Initial Cost to Company, Land	978
Initial Cost to Company, Buildings and Improvements	6,426
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	20,078
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,957
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	25,525
Gross Amount at Which Carried at Close of January 31, 2013, Total	27,482
Accumulated Depreciation at January 31, 2013	2,516
Date of Construction/Acquisition	2006
Office Buildings and Hotel [Member] | 8030 Lamon (J) [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Skokie, IL
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	1,325
Initial Cost to Company, Buildings and Improvements	17,376
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	101
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,325
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	17,477
Gross Amount at Which Carried at Close of January 31, 2013, Total	18,802
Accumulated Depreciation at January 31, 2013	1,055
Date of Construction/Acquisition	2010
Office Buildings and Hotel [Member] | 8045 Lamon (Q) [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Skokie, IL
Amount of Encumbrance at January 31,2013	19,082
Initial Cost to Company, Land	3,301
Initial Cost to Company, Buildings and Improvements	21,198
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	28,486
Gross Amount at Which Carried at Close of January 31, 2013, Land	6,601
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	46,384
Gross Amount at Which Carried at Close of January 31, 2013, Total	52,985
Accumulated Depreciation at January 31, 2013	5,264
Date of Construction/Acquisition	2007
Office Buildings and Hotel [Member] | Johns Hopkins - 855 North Wolfe Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Baltimore, MD
Amount of Encumbrance at January 31,2013	70,871
Initial Cost to Company, Land	7,314
Initial Cost to Company, Buildings and Improvements	76,318
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	11,579
Gross Amount at Which Carried at Close of January 31, 2013, Land	7,314
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	87,897
Gross Amount at Which Carried at Close of January 31, 2013, Total	95,211
Accumulated Depreciation at January 31, 2013	8,022
Date of Construction/Acquisition	2008
Office Buildings and Hotel [Member] | Johns Hopkins Parking Garage [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Baltimore, MD
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	1,600
Initial Cost to Company, Buildings and Improvements	26,185
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,600
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	26,185
Gross Amount at Which Carried at Close of January 31, 2013, Total	27,785
Accumulated Depreciation at January 31, 2013	87
Date of Construction/Acquisition	2012
Office Buildings and Hotel [Member] | Mesa del Sol - 5600 University SE [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Albuquerque, NM
Amount of Encumbrance at January 31,2013	606
Initial Cost to Company, Land	868
Initial Cost to Company, Buildings and Improvements	4,625
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	868
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	4,625
Gross Amount at Which Carried at Close of January 31, 2013, Total	5,493
Accumulated Depreciation at January 31, 2013	1,521
Date of Construction/Acquisition	2006
Office Buildings and Hotel [Member] | Mesa del Sol - Aperture Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Albuquerque, NM
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	834
Initial Cost to Company, Buildings and Improvements	3,010
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	834
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	3,010
Gross Amount at Which Carried at Close of January 31, 2013, Total	3,844
Accumulated Depreciation at January 31, 2013	920
Date of Construction/Acquisition	2008
Office Buildings and Hotel [Member] | Mesa del Sol - Fidelity [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Albuquerque, NM
Amount of Encumbrance at January 31,2013	23,284
Initial Cost to Company, Land	5,003
Initial Cost to Company, Buildings and Improvements	29,872
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	5,003
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	29,872
Gross Amount at Which Carried at Close of January 31, 2013, Total	34,875
Accumulated Depreciation at January 31, 2013	2,003
Date of Construction/Acquisition	2008
Office Buildings and Hotel [Member] | New York Times [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Manhattan, NY
Amount of Encumbrance at January 31,2013	640,000
Initial Cost to Company, Land	91,737
Initial Cost to Company, Buildings and Improvements	375,931
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	137,269
Gross Amount at Which Carried at Close of January 31, 2013, Land	141,479
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	463,458
Gross Amount at Which Carried at Close of January 31, 2013, Total	604,937
Accumulated Depreciation at January 31, 2013	49,100
Date of Construction/Acquisition	2007
Office Buildings and Hotel [Member] | Nine MetroTech Center North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	61,996
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	64,303
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	4,250
Gross Amount at Which Carried at Close of January 31, 2013, Land	380
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	68,173
Gross Amount at Which Carried at Close of January 31, 2013, Total	68,553
Accumulated Depreciation at January 31, 2013	22,039
Date of Construction/Acquisition	1997
Office Buildings and Hotel [Member] | One MetroTech Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	166,480
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	212,153
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	51,596
Gross Amount at Which Carried at Close of January 31, 2013, Land	23,543
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	240,206
Gross Amount at Which Carried at Close of January 31, 2013, Total	263,749
Accumulated Depreciation at January 31, 2013	101,153
Date of Construction/Acquisition	1991
Office Buildings and Hotel [Member] | One Pierrepont Plaza [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	3,907
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	86,863
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	96,180
Gross Amount at Which Carried at Close of January 31, 2013, Land	558
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	182,485
Gross Amount at Which Carried at Close of January 31, 2013, Total	183,043
Accumulated Depreciation at January 31, 2013	99,097
Date of Construction/Acquisition	1988
Office Buildings and Hotel [Member] | Post Office Plaza (MK Ferguson) [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Cleveland, OH
Amount of Encumbrance at January 31,2013	15,197
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	57,213
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	24,219
Gross Amount at Which Carried at Close of January 31, 2013, Land	0
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	81,432
Gross Amount at Which Carried at Close of January 31, 2013, Total	81,432
Accumulated Depreciation at January 31, 2013	37,112
Date of Construction/Acquisition	1990
Office Buildings and Hotel [Member] | Richmond Office Park [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Richmond, VA
Amount of Encumbrance at January 31,2013	64,189
Initial Cost to Company, Land	11,766
Initial Cost to Company, Buildings and Improvements	88,632
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	6,533
Gross Amount at Which Carried at Close of January 31, 2013, Land	11,766
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	95,165
Gross Amount at Which Carried at Close of January 31, 2013, Total	106,931
Accumulated Depreciation at January 31, 2013	14,171
Date of Construction/Acquisition	2007
Office Buildings and Hotel [Member] | Sheraton Station Square Hotel [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Pittsburgh, PA
Amount of Encumbrance at January 31,2013	42,615
Initial Cost to Company, Land	2,172
Initial Cost to Company, Buildings and Improvements	53,153
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	4,656
Gross Amount at Which Carried at Close of January 31, 2013, Land	2,180
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	57,801
Gross Amount at Which Carried at Close of January 31, 2013, Total	59,981
Accumulated Depreciation at January 31, 2013	19,239
Date of Construction/Acquisition	1998
Office Buildings and Hotel [Member] | Skylight Office Tower [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Cleveland, OH
Amount of Encumbrance at January 31,2013	27,910
Initial Cost to Company, Land	2,500
Initial Cost to Company, Buildings and Improvements	32,695
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	33,009
Gross Amount at Which Carried at Close of January 31, 2013, Land	0
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	68,204
Gross Amount at Which Carried at Close of January 31, 2013, Total	68,204
Accumulated Depreciation at January 31, 2013	35,119
Date of Construction/Acquisition	1991
Office Buildings and Hotel [Member] | Stapleton - 3055 Roslyn [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Denver, CO
Amount of Encumbrance at January 31,2013	4,554
Initial Cost to Company, Land	225
Initial Cost to Company, Buildings and Improvements	7,523
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	877
Gross Amount at Which Carried at Close of January 31, 2013, Land	225
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	8,400
Gross Amount at Which Carried at Close of January 31, 2013, Total	8,625
Accumulated Depreciation at January 31, 2013	1,033
Date of Construction/Acquisition	2006
Office Buildings and Hotel [Member] | Ten MetroTech Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	40,000
Initial Cost to Company, Land	3,680
Initial Cost to Company, Buildings and Improvements	95,234
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	3,856
Gross Amount at Which Carried at Close of January 31, 2013, Land	9,265
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	93,505
Gross Amount at Which Carried at Close of January 31, 2013, Total	102,770
Accumulated Depreciation at January 31, 2013	48,202
Date of Construction/Acquisition	1992
Office Buildings and Hotel [Member] | Terminal Tower [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Cleveland, OH
Amount of Encumbrance at January 31,2013	5,500
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	29,422
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	79,919
Gross Amount at Which Carried at Close of January 31, 2013, Land	0
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	109,341
Gross Amount at Which Carried at Close of January 31, 2013, Total	109,341
Accumulated Depreciation at January 31, 2013	54,143
Date of Construction/Acquisition	1983
Office Buildings and Hotel [Member] | Twelve MetroTech Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	45,000
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	42,344
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	16,141
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,847
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	56,638
Gross Amount at Which Carried at Close of January 31, 2013, Total	58,485
Accumulated Depreciation at January 31, 2013	8,938
Date of Construction/Acquisition	2004
Office Buildings and Hotel [Member] | Two MetroTech Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	75,414
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	155,280
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	32,352
Gross Amount at Which Carried at Close of January 31, 2013, Land	7,137
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	180,495
Gross Amount at Which Carried at Close of January 31, 2013, Total	187,632
Accumulated Depreciation at January 31, 2013	64,744
Date of Construction/Acquisition	1990
Office Buildings and Hotel [Member] | University of Pennsylvania [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Philadelphia, PA
Amount of Encumbrance at January 31,2013	49,563
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	41,146
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	10,665
Gross Amount at Which Carried at Close of January 31, 2013, Land	0
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	51,811
Gross Amount at Which Carried at Close of January 31, 2013, Total	51,811
Accumulated Depreciation at January 31, 2013	8,389
Date of Construction/Acquisition	2004
Office Buildings and Hotel [Member] | Miscellaneous Investments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Various
Amount of Encumbrance at January 31,2013	885
Initial Cost to Company, Land	2,424
Initial Cost to Company, Buildings and Improvements	71,887
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	2,965
Gross Amount at Which Carried at Close of January 31, 2013, Land	2,424
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	74,852
Gross Amount at Which Carried at Close of January 31, 2013, Total	77,276
Accumulated Depreciation at January 31, 2013	19,250
Date of Construction/Acquisition Miscellaneous	Various
Retail [Member]
Real Estate and Accumulated Depreciation [Line Items]
Amount of Encumbrance at January 31,2013	1,927,409
Initial Cost to Company, Land	449,795
Initial Cost to Company, Buildings and Improvements	2,175,119
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	564,336
Gross Amount at Which Carried at Close of January 31, 2013, Land	532,785
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	2,656,465
Gross Amount at Which Carried at Close of January 31, 2013, Total	3,189,250
Accumulated Depreciation at January 31, 2013	532,433
Retail [Member] | Miscellaneous Investments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Various
Amount of Encumbrance at January 31,2013	17,009
Initial Cost to Company, Land	14,222
Initial Cost to Company, Buildings and Improvements	24,287
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	9,766
Gross Amount at Which Carried at Close of January 31, 2013, Land	21,102
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	27,173
Gross Amount at Which Carried at Close of January 31, 2013, Total	48,275
Accumulated Depreciation at January 31, 2013	7,964
Date of Construction/Acquisition Miscellaneous	Various
Retail [Member] | Antelope Valley Mall [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Palmdale, CA
Amount of Encumbrance at January 31,2013	96,158
Initial Cost to Company, Land	1,492
Initial Cost to Company, Buildings and Improvements	58,028
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	69,120
Gross Amount at Which Carried at Close of January 31, 2013, Land	10,078
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	118,562
Gross Amount at Which Carried at Close of January 31, 2013, Total	128,640
Accumulated Depreciation at January 31, 2013	40,561
Date of Construction/Acquisition	1999
Retail [Member] | Atlantic Center Site V [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	3,641
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	3,238
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,485
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,047
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	3,676
Gross Amount at Which Carried at Close of January 31, 2013, Total	4,723
Accumulated Depreciation at January 31, 2013	1,147
Date of Construction/Acquisition	1998
Retail [Member] | Avenue at Tower City Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Cleveland, OH
Amount of Encumbrance at January 31,2013	25,557
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	174,726
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	24,784
Gross Amount at Which Carried at Close of January 31, 2013, Land	192
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	199,318
Gross Amount at Which Carried at Close of January 31, 2013, Total	199,510
Accumulated Depreciation at January 31, 2013	96,235
Date of Construction/Acquisition	1990
Retail [Member] | Ballston Common Mall [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Arlington, VA
Amount of Encumbrance at January 31,2013	45,924
Initial Cost to Company, Land	170
Initial Cost to Company, Buildings and Improvements	18,069
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	66,838
Gross Amount at Which Carried at Close of January 31, 2013, Land	442
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	84,635
Gross Amount at Which Carried at Close of January 31, 2013, Total	85,077
Accumulated Depreciation at January 31, 2013	42,995
Date of Construction/Acquisition	1986
Retail [Member] | Brooklyn Commons [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	21,967
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	23,794
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,688
Gross Amount at Which Carried at Close of January 31, 2013, Land	20,017
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	5,465
Gross Amount at Which Carried at Close of January 31, 2013, Total	25,482
Accumulated Depreciation at January 31, 2013	1,335
Date of Construction/Acquisition	2004
Retail [Member] | Galleria at Sunset [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Henderson, NV
Amount of Encumbrance at January 31,2013	149,604
Initial Cost to Company, Land	14,965
Initial Cost to Company, Buildings and Improvements	161,893
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	884
Gross Amount at Which Carried at Close of January 31, 2013, Land	30,799
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	146,943
Gross Amount at Which Carried at Close of January 31, 2013, Total	177,742
Accumulated Depreciation at January 31, 2013	37,811
Date of Construction/Acquisition	1996
Retail [Member] | Mall at Robinson [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Pittsburgh, PA
Amount of Encumbrance at January 31,2013	77,520
Initial Cost to Company, Land	5,475
Initial Cost to Company, Buildings and Improvements	101,086
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,383
Gross Amount at Which Carried at Close of January 31, 2013, Land	6,151
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	101,793
Gross Amount at Which Carried at Close of January 31, 2013, Total	107,944
Accumulated Depreciation at January 31, 2013	30,114
Date of Construction/Acquisition	2001
Retail [Member] | Northfield at Stapleton [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Denver, CO
Amount of Encumbrance at January 31,2013	43,401
Initial Cost to Company, Land	4,830
Initial Cost to Company, Buildings and Improvements	80,687
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	84,132
Gross Amount at Which Carried at Close of January 31, 2013, Land	25,235
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	144,414
Gross Amount at Which Carried at Close of January 31, 2013, Total	169,649
Accumulated Depreciation at January 31, 2013	24,965
Date of Construction/Acquisition	2005
Retail [Member] | Orchard Town Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Westminster, CO
Amount of Encumbrance at January 31,2013	62,939
Initial Cost to Company, Land	31,129
Initial Cost to Company, Buildings and Improvements	99,139
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	16,850
Gross Amount at Which Carried at Close of January 31, 2013, Land	30,945
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	116,173
Gross Amount at Which Carried at Close of January 31, 2013, Total	147,118
Accumulated Depreciation at January 31, 2013	16,355
Date of Construction/Acquisition	2008
Retail [Member] | Promenade Bolingbrook [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Bolingbrook, IL
Amount of Encumbrance at January 31,2013	74,621
Initial Cost to Company, Land	20,271
Initial Cost to Company, Buildings and Improvements	95,390
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	21,656
Gross Amount at Which Carried at Close of January 31, 2013, Land	21,031
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	116,286
Gross Amount at Which Carried at Close of January 31, 2013, Total	137,317
Accumulated Depreciation at January 31, 2013	17,791
Date of Construction/Acquisition	2007
Retail [Member] | Promenade in Temecula [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Temecula, CA
Amount of Encumbrance at January 31,2013	164,105
Initial Cost to Company, Land	5,837
Initial Cost to Company, Buildings and Improvements	59,319
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	145,294
Gross Amount at Which Carried at Close of January 31, 2013, Land	17,574
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	192,876
Gross Amount at Which Carried at Close of January 31, 2013, Total	210,450
Accumulated Depreciation at January 31, 2013	37,983
Date of Construction/Acquisition	1999
Retail [Member] | Quartermaster Plaza [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Philadelphia, PA
Amount of Encumbrance at January 31,2013	66,018
Initial Cost to Company, Land	36,443
Initial Cost to Company, Buildings and Improvements	32,325
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,348
Gross Amount at Which Carried at Close of January 31, 2013, Land	35,340
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	34,776
Gross Amount at Which Carried at Close of January 31, 2013, Total	70,116
Accumulated Depreciation at January 31, 2013	12,083
Date of Construction/Acquisition	2004
Retail [Member] | Shops at Wiregrass [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Tampa, FL
Amount of Encumbrance at January 31,2013	104,325
Initial Cost to Company, Land	28,842
Initial Cost to Company, Buildings and Improvements	109,587
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,373
Gross Amount at Which Carried at Close of January 31, 2013, Land	33,786
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	106,016
Gross Amount at Which Carried at Close of January 31, 2013, Total	139,802
Accumulated Depreciation at January 31, 2013	15,084
Date of Construction/Acquisition	2008
Retail [Member] | Short Pump Town Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Richmond, VA
Amount of Encumbrance at January 31,2013	149,649
Initial Cost to Company, Land	20,023
Initial Cost to Company, Buildings and Improvements	136,172
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	14,133
Gross Amount at Which Carried at Close of January 31, 2013, Land	15,124
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	155,204
Gross Amount at Which Carried at Close of January 31, 2013, Total	170,328
Accumulated Depreciation at January 31, 2013	29,466
Date of Construction/Acquisition	2003
Retail [Member] | South Bay Galleria [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Redondo Beach, CA
Amount of Encumbrance at January 31,2013	119,049
Initial Cost to Company, Land	1,297
Initial Cost to Company, Buildings and Improvements	108,236
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	28,965
Gross Amount at Which Carried at Close of January 31, 2013, Land	8,144
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	130,354
Gross Amount at Which Carried at Close of January 31, 2013, Total	138,498
Accumulated Depreciation at January 31, 2013	31,499
Date of Construction/Acquisition	1985
Retail [Member] | Station Square [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Pittsburgh, PA
Amount of Encumbrance at January 31,2013	24,814
Initial Cost to Company, Land	5,989
Initial Cost to Company, Buildings and Improvements	27,519
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	19,154
Gross Amount at Which Carried at Close of January 31, 2013, Land	6,279
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	46,383
Gross Amount at Which Carried at Close of January 31, 2013, Total	52,662
Accumulated Depreciation at January 31, 2013	20,317
Date of Construction/Acquisition	1994
Retail [Member] | The Yards - Boilermaker Shops [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Washington, D.C.
Amount of Encumbrance at January 31,2013	10,267
Initial Cost to Company, Land	529
Initial Cost to Company, Buildings and Improvements	12,468
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	529
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	12,468
Gross Amount at Which Carried at Close of January 31, 2013, Total	12,997
Accumulated Depreciation at January 31, 2013	31
Date of Construction/Acquisition	2012
Retail [Member] | Tower City Parking [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Cleveland, OH
Amount of Encumbrance at January 31,2013	1,443
Initial Cost to Company, Land	2,317
Initial Cost to Company, Buildings and Improvements	11,789
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	15,325
Gross Amount at Which Carried at Close of January 31, 2013, Land	2,036
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	27,395
Gross Amount at Which Carried at Close of January 31, 2013, Total	29,431
Accumulated Depreciation at January 31, 2013	11,281
Date of Construction/Acquisition	1990
Retail [Member] | Victoria Gardens [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Rancho Cucamonga, CA
Amount of Encumbrance at January 31,2013	197,398
Initial Cost to Company, Land	19,272
Initial Cost to Company, Buildings and Improvements	175,662
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	40,158
Gross Amount at Which Carried at Close of January 31, 2013, Land	10,242
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	224,850
Gross Amount at Which Carried at Close of January 31, 2013, Total	235,092
Accumulated Depreciation at January 31, 2013	35,598
Date of Construction/Acquisition	2004
Retail [Member] | Westchester's Ridge Hill [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Yonkers, NY
Amount of Encumbrance at January 31,2013	472,000
Initial Cost to Company, Land	236,692
Initial Cost to Company, Buildings and Improvements	661,705
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	236,692
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	661,705
Gross Amount at Which Carried at Close of January 31, 2013, Total	898,397
Accumulated Depreciation at January 31, 2013	21,818
Date of Construction/Acquisition	2011
Arena [Member] | Barclays Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	429,041
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	890,213
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	0
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	890,213
Gross Amount at Which Carried at Close of January 31, 2013, Total	890,213
Accumulated Depreciation at January 31, 2013	8,699
Date of Construction/Acquisition	2012
Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Amount of Encumbrance at January 31,2013	1,001,551
Initial Cost to Company, Land	93,348
Initial Cost to Company, Buildings and Improvements	1,329,643
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	167,655
Gross Amount at Which Carried at Close of January 31, 2013, Land	97,353
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	1,493,293
Gross Amount at Which Carried at Close of January 31, 2013, Total	1,590,646
Accumulated Depreciation at January 31, 2013	351,982
Apartments [Member] | Miscellaneous Investments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Various
Amount of Encumbrance at January 31,2013	18,457
Initial Cost to Company, Land	966
Initial Cost to Company, Buildings and Improvements	63,581
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	20,363
Gross Amount at Which Carried at Close of January 31, 2013, Land	765
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	84,145
Gross Amount at Which Carried at Close of January 31, 2013, Total	84,910
Accumulated Depreciation at January 31, 2013	16,310
Date of Construction/Acquisition Miscellaneous	Various
Apartments [Member] | 100 Landsdowne Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Cambridge, MA
Amount of Encumbrance at January 31,2013	45,000
Initial Cost to Company, Land	728
Initial Cost to Company, Buildings and Improvements	60,020
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	(145)
Gross Amount at Which Carried at Close of January 31, 2013, Land	819
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	59,784
Gross Amount at Which Carried at Close of January 31, 2013, Total	60,603
Accumulated Depreciation at January 31, 2013	11,618
Date of Construction/Acquisition	2005
Apartments [Member] | 1251 S. Michigan [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Chicago, IL
Amount of Encumbrance at January 31,2013	9,521
Initial Cost to Company, Land	97
Initial Cost to Company, Buildings and Improvements	13,978
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	758
Gross Amount at Which Carried at Close of January 31, 2013, Land	106
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	14,727
Gross Amount at Which Carried at Close of January 31, 2013, Total	14,833
Accumulated Depreciation at January 31, 2013	2,405
Date of Construction/Acquisition	2006
Apartments [Member] | American Cigar Company [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Richmond, VA
Amount of Encumbrance at January 31,2013	11,530
Initial Cost to Company, Land	1,395
Initial Cost to Company, Buildings and Improvements	23,533
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	422
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,356
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	23,994
Gross Amount at Which Carried at Close of January 31, 2013, Total	25,350
Accumulated Depreciation at January 31, 2013	3,694
Date of Construction/Acquisition	2000
Apartments [Member] | Ashton Mill [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Cumberland, RI
Amount of Encumbrance at January 31,2013	17,290
Initial Cost to Company, Land	2,885
Initial Cost to Company, Buildings and Improvements	33,844
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	9,846
Gross Amount at Which Carried at Close of January 31, 2013, Land	3,242
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	43,333
Gross Amount at Which Carried at Close of January 31, 2013, Total	46,575
Accumulated Depreciation at January 31, 2013	7,503
Date of Construction/Acquisition	2005
Apartments [Member] | Botanica Eastbridge [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Denver, CO
Amount of Encumbrance at January 31,2013	10,302
Initial Cost to Company, Land	765
Initial Cost to Company, Buildings and Improvements	13,698
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	765
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	13,698
Gross Amount at Which Carried at Close of January 31, 2013, Total	14,463
Accumulated Depreciation at January 31, 2013	213
Date of Construction/Acquisition	2012
Apartments [Member] | Brookview Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Dayton, OH
Amount of Encumbrance at January 31,2013	2,336
Initial Cost to Company, Land	155
Initial Cost to Company, Buildings and Improvements	4,588
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	161
Gross Amount at Which Carried at Close of January 31, 2013, Land	155
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	4,749
Gross Amount at Which Carried at Close of January 31, 2013, Total	4,904
Accumulated Depreciation at January 31, 2013	3,459
Date of Construction/Acquisition	1979
Apartments [Member] | Cameron Kinney [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Richmond, VA
Amount of Encumbrance at January 31,2013	18,000
Initial Cost to Company, Land	2,340
Initial Cost to Company, Buildings and Improvements	23,206
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	3,322
Gross Amount at Which Carried at Close of January 31, 2013, Land	2,468
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	26,400
Gross Amount at Which Carried at Close of January 31, 2013, Total	28,868
Accumulated Depreciation at January 31, 2013	3,885
Date of Construction/Acquisition	2007
Apartments [Member] | Cedar Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Lansing, MI
Amount of Encumbrance at January 31,2013	3,993
Initial Cost to Company, Land	399
Initial Cost to Company, Buildings and Improvements	7,000
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	193
Gross Amount at Which Carried at Close of January 31, 2013, Land	399
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	7,193
Gross Amount at Which Carried at Close of January 31, 2013, Total	7,592
Accumulated Depreciation at January 31, 2013	3,370
Date of Construction/Acquisition	1974
Apartments [Member] | Consolidated-Carolina [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Richmond, VA
Amount of Encumbrance at January 31,2013	21,290
Initial Cost to Company, Land	1,028
Initial Cost to Company, Buildings and Improvements	30,425
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,382
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,032
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	31,803
Gross Amount at Which Carried at Close of January 31, 2013, Total	32,835
Accumulated Depreciation at January 31, 2013	6,607
Date of Construction/Acquisition	2003
Apartments [Member] | Cutter's Ridge at Tobacco Row [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Richmond, VA
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	389
Initial Cost to Company, Buildings and Improvements	4,356
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	(128)
Gross Amount at Which Carried at Close of January 31, 2013, Land	389
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	4,228
Gross Amount at Which Carried at Close of January 31, 2013, Total	4,617
Accumulated Depreciation at January 31, 2013	948
Date of Construction/Acquisition	2006
Apartments [Member] | Drake [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Philadelphia, PA
Amount of Encumbrance at January 31,2013	27,696
Initial Cost to Company, Land	1,353
Initial Cost to Company, Buildings and Improvements	38,104
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	8,132
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,353
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	46,236
Gross Amount at Which Carried at Close of January 31, 2013, Total	47,589
Accumulated Depreciation at January 31, 2013	12,283
Date of Construction/Acquisition	1998
Apartments [Member] | Easthaven at the Village [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Beachwood, OH
Amount of Encumbrance at January 31,2013	26,126
Initial Cost to Company, Land	7,919
Initial Cost to Company, Buildings and Improvements	39,768
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	7,546
Gross Amount at Which Carried at Close of January 31, 2013, Land	8,087
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	47,146
Gross Amount at Which Carried at Close of January 31, 2013, Total	55,233
Accumulated Depreciation at January 31, 2013	17,651
Date of Construction/Acquisition	1994
Apartments [Member] | Forest Trace [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Lauderhill, FL
Amount of Encumbrance at January 31,2013	38,907
Initial Cost to Company, Land	4,356
Initial Cost to Company, Buildings and Improvements	41,505
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,826
Gross Amount at Which Carried at Close of January 31, 2013, Land	4,512
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	43,175
Gross Amount at Which Carried at Close of January 31, 2013, Total	47,687
Accumulated Depreciation at January 31, 2013	12,416
Date of Construction/Acquisition	2000
Apartments [Member] | Foundry Lofts [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Washington, D.C.
Amount of Encumbrance at January 31,2013	45,626
Initial Cost to Company, Land	2,086
Initial Cost to Company, Buildings and Improvements	52,806
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	3,265
Gross Amount at Which Carried at Close of January 31, 2013, Land	2,086
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	56,071
Gross Amount at Which Carried at Close of January 31, 2013, Total	58,157
Accumulated Depreciation at January 31, 2013	1,872
Date of Construction/Acquisition	2011
Apartments [Member] | Grand Lowry Lofts [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Denver, CO
Amount of Encumbrance at January 31,2013	17,485
Initial Cost to Company, Land	1,448
Initial Cost to Company, Buildings and Improvements	22,726
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	2,058
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,605
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	24,627
Gross Amount at Which Carried at Close of January 31, 2013, Total	26,232
Accumulated Depreciation at January 31, 2013	4,803
Date of Construction/Acquisition	2000
Apartments [Member] | Hamel Mill Lofts [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Haverhill, MA
Amount of Encumbrance at January 31,2013	41,361
Initial Cost to Company, Land	3,974
Initial Cost to Company, Buildings and Improvements	72,902
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	621
Gross Amount at Which Carried at Close of January 31, 2013, Land	3,974
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	73,523
Gross Amount at Which Carried at Close of January 31, 2013, Total	77,497
Accumulated Depreciation at January 31, 2013	6,620
Date of Construction/Acquisition	2008
Apartments [Member] | Heritage [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	San Diego, CA
Amount of Encumbrance at January 31,2013	22,919
Initial Cost to Company, Land	7,433
Initial Cost to Company, Buildings and Improvements	42,202
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	3,491
Gross Amount at Which Carried at Close of January 31, 2013, Land	7,438
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	45,688
Gross Amount at Which Carried at Close of January 31, 2013, Total	53,126
Accumulated Depreciation at January 31, 2013	15,084
Date of Construction/Acquisition	2002
Apartments [Member] | Hummingbird Pointe (Parmatown Towers and Gardens) [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Parma, OH
Amount of Encumbrance at January 31,2013	6,185
Initial Cost to Company, Land	330
Initial Cost to Company, Buildings and Improvements	5,059
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	15,850
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,199
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	20,040
Gross Amount at Which Carried at Close of January 31, 2013, Total	21,239
Accumulated Depreciation at January 31, 2013	7,846
Date of Construction/Acquisition	1972
Apartments [Member] | Independence Place I [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Parma Heights, OH
Amount of Encumbrance at January 31,2013	4,207
Initial Cost to Company, Land	210
Initial Cost to Company, Buildings and Improvements	6,671
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	772
Gross Amount at Which Carried at Close of January 31, 2013, Land	215
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	7,438
Gross Amount at Which Carried at Close of January 31, 2013, Total	7,653
Accumulated Depreciation at January 31, 2013	3,883
Date of Construction/Acquisition	1973
Apartments [Member] | Independence Place II [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Parma Heights, OH
Amount of Encumbrance at January 31,2013	3,366
Initial Cost to Company, Land	498
Initial Cost to Company, Buildings and Improvements	3,931
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,475
Gross Amount at Which Carried at Close of January 31, 2013, Land	507
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	5,397
Gross Amount at Which Carried at Close of January 31, 2013, Total	5,904
Accumulated Depreciation at January 31, 2013	1,538
Date of Construction/Acquisition	2003
Apartments [Member] | Kennedy Biscuit Lofts [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Cambridge, MA
Amount of Encumbrance at January 31,2013	20,600
Initial Cost to Company, Land	716
Initial Cost to Company, Buildings and Improvements	23,645
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	4,104
Gross Amount at Which Carried at Close of January 31, 2013, Land	719
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	27,746
Gross Amount at Which Carried at Close of January 31, 2013, Total	28,465
Accumulated Depreciation at January 31, 2013	14,567
Date of Construction/Acquisition	1990
Apartments [Member] | Knolls [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Orange, CA
Amount of Encumbrance at January 31,2013	32,520
Initial Cost to Company, Land	53
Initial Cost to Company, Buildings and Improvements	23,759
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	390
Gross Amount at Which Carried at Close of January 31, 2013, Land	53
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	24,149
Gross Amount at Which Carried at Close of January 31, 2013, Total	24,202
Accumulated Depreciation at January 31, 2013	10,281
Date of Construction/Acquisition	1995
Apartments [Member] | Lofts 23 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Cambridge, MA
Amount of Encumbrance at January 31,2013	6,170
Initial Cost to Company, Land	221
Initial Cost to Company, Buildings and Improvements	17,026
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	52
Gross Amount at Which Carried at Close of January 31, 2013, Land	314
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	16,985
Gross Amount at Which Carried at Close of January 31, 2013, Total	17,299
Accumulated Depreciation at January 31, 2013	3,738
Date of Construction/Acquisition	2005
Apartments [Member] | Lofts at 1835 Arch [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Philadelphia, PA
Amount of Encumbrance at January 31,2013	38,291
Initial Cost to Company, Land	2,076
Initial Cost to Company, Buildings and Improvements	27,430
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	12,178
Gross Amount at Which Carried at Close of January 31, 2013, Land	2,082
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	39,602
Gross Amount at Which Carried at Close of January 31, 2013, Total	41,684
Accumulated Depreciation at January 31, 2013	9,673
Date of Construction/Acquisition	2001
Apartments [Member] | Lucky Strike [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Richmond, VA
Amount of Encumbrance at January 31,2013	15,278
Initial Cost to Company, Land	1,105
Initial Cost to Company, Buildings and Improvements	34,095
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	31
Gross Amount at Which Carried at Close of January 31, 2013, Land	3,019
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	32,212
Gross Amount at Which Carried at Close of January 31, 2013, Total	35,231
Accumulated Depreciation at January 31, 2013	4,697
Date of Construction/Acquisition	2008
Apartments [Member] | Mercantile Place on Main [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Dallas, TX
Amount of Encumbrance at January 31,2013	37,592
Initial Cost to Company, Land	8,876
Initial Cost to Company, Buildings and Improvements	75,478
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	5,099
Gross Amount at Which Carried at Close of January 31, 2013, Land	8,795
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	80,658
Gross Amount at Which Carried at Close of January 31, 2013, Total	89,453
Accumulated Depreciation at January 31, 2013	11,782
Date of Construction/Acquisition	2008
Apartments [Member] | Metro 417 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Los Angeles, CA
Amount of Encumbrance at January 31,2013	49,874
Initial Cost to Company, Land	8,545
Initial Cost to Company, Buildings and Improvements	67,326
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	4,155
Gross Amount at Which Carried at Close of January 31, 2013, Land	8,547
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	71,479
Gross Amount at Which Carried at Close of January 31, 2013, Total	80,026
Accumulated Depreciation at January 31, 2013	12,181
Date of Construction/Acquisition	2005
Apartments [Member] | Metropolitan [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Los Angeles, CA
Amount of Encumbrance at January 31,2013	38,900
Initial Cost to Company, Land	4,420
Initial Cost to Company, Buildings and Improvements	36,557
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	9,549
Gross Amount at Which Carried at Close of January 31, 2013, Land	4,463
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	46,063
Gross Amount at Which Carried at Close of January 31, 2013, Total	50,526
Accumulated Depreciation at January 31, 2013	21,547
Date of Construction/Acquisition	1989
Apartments [Member] | Midtown Towers [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Parma, OH
Amount of Encumbrance at January 31,2013	13,401
Initial Cost to Company, Land	1,215
Initial Cost to Company, Buildings and Improvements	11,091
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	10,940
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,293
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	21,953
Gross Amount at Which Carried at Close of January 31, 2013, Total	23,246
Accumulated Depreciation at January 31, 2013	8,768
Date of Construction/Acquisition	1969
Apartments [Member] | Millender Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Detroit, MI
Amount of Encumbrance at January 31,2013	9,049
Initial Cost to Company, Land	1,247
Initial Cost to Company, Buildings and Improvements	16,847
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	691
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,247
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	17,538
Gross Amount at Which Carried at Close of January 31, 2013, Total	18,785
Accumulated Depreciation at January 31, 2013	9,933
Date of Construction/Acquisition	1985
Apartments [Member] | Museum Towers [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Philadelphia, PA
Amount of Encumbrance at January 31,2013	31,864
Initial Cost to Company, Land	3,474
Initial Cost to Company, Buildings and Improvements	18,158
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	6,213
Gross Amount at Which Carried at Close of January 31, 2013, Land	3,909
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	23,936
Gross Amount at Which Carried at Close of January 31, 2013, Total	27,845
Accumulated Depreciation at January 31, 2013	8,245
Date of Construction/Acquisition	1997
Apartments [Member] | North Church Towers [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Parma Heights, OH
Amount of Encumbrance at January 31,2013	5,488
Initial Cost to Company, Land	789
Initial Cost to Company, Buildings and Improvements	4,037
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,034
Gross Amount at Which Carried at Close of January 31, 2013, Land	789
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	5,071
Gross Amount at Which Carried at Close of January 31, 2013, Total	5,860
Accumulated Depreciation at January 31, 2013	976
Date of Construction/Acquisition	2009
Apartments [Member] | One Franklintown [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Philadelphia, PA
Amount of Encumbrance at January 31,2013	38,371
Initial Cost to Company, Land	1,658
Initial Cost to Company, Buildings and Improvements	31,489
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	8,364
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,741
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	39,770
Gross Amount at Which Carried at Close of January 31, 2013, Total	41,511
Accumulated Depreciation at January 31, 2013	19,031
Date of Construction/Acquisition	1988
Apartments [Member] | Pavilion [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Chicago, IL
Amount of Encumbrance at January 31,2013	54,226
Initial Cost to Company, Land	5,250
Initial Cost to Company, Buildings and Improvements	29,505
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	13,339
Gross Amount at Which Carried at Close of January 31, 2013, Land	5,267
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	42,827
Gross Amount at Which Carried at Close of January 31, 2013, Total	48,094
Accumulated Depreciation at January 31, 2013	10,851
Date of Construction/Acquisition	1992
Apartments [Member] | Perrytown Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Pittsburgh, PA
Amount of Encumbrance at January 31,2013	4,735
Initial Cost to Company, Land	463
Initial Cost to Company, Buildings and Improvements	6,898
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	36
Gross Amount at Which Carried at Close of January 31, 2013, Land	463
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	6,934
Gross Amount at Which Carried at Close of January 31, 2013, Total	7,397
Accumulated Depreciation at January 31, 2013	3,765
Date of Construction/Acquisition	1973
Apartments [Member] | Presidio Landmark [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	San Francisco, CA
Amount of Encumbrance at January 31,2013	57,123
Initial Cost to Company, Land	2,060
Initial Cost to Company, Buildings and Improvements	92,687
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,854
Gross Amount at Which Carried at Close of January 31, 2013, Land	2,060
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	94,541
Gross Amount at Which Carried at Close of January 31, 2013, Total	96,601
Accumulated Depreciation at January 31, 2013	7,254
Date of Construction/Acquisition	2010
Apartments [Member] | Queenswood [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Corona, NY
Amount of Encumbrance at January 31,2013	28,729
Initial Cost to Company, Land	321
Initial Cost to Company, Buildings and Improvements	39,243
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	749
Gross Amount at Which Carried at Close of January 31, 2013, Land	327
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	39,986
Gross Amount at Which Carried at Close of January 31, 2013, Total	40,313
Accumulated Depreciation at January 31, 2013	16,603
Date of Construction/Acquisition	1990
Apartments [Member] | Sky55 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Chicago, IL
Amount of Encumbrance at January 31,2013	67,970
Initial Cost to Company, Land	3,965
Initial Cost to Company, Buildings and Improvements	80,930
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	249
Gross Amount at Which Carried at Close of January 31, 2013, Land	4,011
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	81,133
Gross Amount at Which Carried at Close of January 31, 2013, Total	85,144
Accumulated Depreciation at January 31, 2013	15,991
Date of Construction/Acquisition	2006
Apartments [Member] | The Aster Town Center [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Denver, CO
Amount of Encumbrance at January 31,2013	8,364
Initial Cost to Company, Land	487
Initial Cost to Company, Buildings and Improvements	9,901
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	487
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	9,901
Gross Amount at Which Carried at Close of January 31, 2013, Total	10,388
Accumulated Depreciation at January 31, 2013	264
Date of Construction/Acquisition	2012
Apartments [Member] | Town Center ( Botanica on the Green & Crescent Flats) [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Denver, CO
Amount of Encumbrance at January 31,2013	38,633
Initial Cost to Company, Land	3,436
Initial Cost to Company, Buildings and Improvements	63,073
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	3,907
Gross Amount at Which Carried at Close of January 31, 2013, Land	3,358
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	67,058
Gross Amount at Which Carried at Close of January 31, 2013, Total	70,416
Accumulated Depreciation at January 31, 2013	15,032
Date of Construction/Acquisition	2004
Apartments [Member] | Wilson Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Dallas, TX
Amount of Encumbrance at January 31,2013	12,776
Initial Cost to Company, Land	2,217
Initial Cost to Company, Buildings and Improvements	16,565
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	3,511
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,937
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	20,356
Gross Amount at Which Carried at Close of January 31, 2013, Total	22,293
Accumulated Depreciation at January 31, 2013	2,795
Date of Construction/Acquisition	2007
Land Held for Development and Sale [Member] | Stapleton [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Denver, CO
Amount of Encumbrance at January 31,2013	9,301
Initial Cost to Company, Land	65,059
Initial Cost to Company, Buildings and Improvements	0
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	65,059
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	0
Gross Amount at Which Carried at Close of January 31, 2013, Total	65,059
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Leasehold Improvements and Other Equipment [Member] | Miscellaneous Investments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Various
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	11,245
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	0
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	11,245
Gross Amount at Which Carried at Close of January 31, 2013, Total	11,245
Accumulated Depreciation at January 31, 2013	8,944
Date of Construction/Acquisition Miscellaneous	Various
Construction Projects [Member] | Miscellaneous Investments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Various
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	132
Initial Cost to Company, Buildings and Improvements	6,656
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	132
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	6,656
Gross Amount at Which Carried at Close of January 31, 2013, Total	6,788
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Construction Projects [Member] | Aster Northfield [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Denver, CO
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	997
Initial Cost to Company, Buildings and Improvements	4,727
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	997
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	4,727
Gross Amount at Which Carried at Close of January 31, 2013, Total	5,724
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Construction Projects [Member] | Brooklyn Atlantic Yards - B2 BKLYN [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	45,000
Initial Cost to Company, Land	55,355
Initial Cost to Company, Buildings and Improvements	0
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	55,355
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	0
Gross Amount at Which Carried at Close of January 31, 2013, Total	55,355
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Construction Projects [Member] | Continental Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Dallas, TX
Amount of Encumbrance at January 31,2013	28,474
Initial Cost to Company, Land	2,512
Initial Cost to Company, Buildings and Improvements	41,604
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	2,512
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	41,604
Gross Amount at Which Carried at Close of January 31, 2013, Total	44,116
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Construction Projects [Member] | Stratford Avenue [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Fairfield, CT
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	2,341
Initial Cost to Company, Buildings and Improvements	3,051
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	2,341
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	3,051
Gross Amount at Which Carried at Close of January 31, 2013, Total	5,392
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Construction Projects [Member] | The Yards - Lumber Shed [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Washington, D.C.
Amount of Encumbrance at January 31,2013	2,449
Initial Cost to Company, Land	306
Initial Cost to Company, Buildings and Improvements	5,602
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	306
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	5,602
Gross Amount at Which Carried at Close of January 31, 2013, Total	5,908
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Construction Projects [Member] | The Yards - Twelve12 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Washington, D.C.
Amount of Encumbrance at January 31,2013	81,837
Initial Cost to Company, Land	4,804
Initial Cost to Company, Buildings and Improvements	20,920
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	4,804
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	20,920
Gross Amount at Which Carried at Close of January 31, 2013, Total	25,724
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Construction Projects [Member] | West Village [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Dallas, TX
Amount of Encumbrance at January 31,2013	6,216
Initial Cost to Company, Land	12,934
Initial Cost to Company, Buildings and Improvements	4,977
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	12,934
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	4,977
Gross Amount at Which Carried at Close of January 31, 2013, Total	17,911
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Development Projects [Member] | Miscellaneous Investments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Various
Amount of Encumbrance at January 31,2013	16,317
Initial Cost to Company, Land	22,416
Initial Cost to Company, Buildings and Improvements	127,256
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	22,416
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	127,256
Gross Amount at Which Carried at Close of January 31, 2013, Total	149,672
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Development Projects [Member] | Brooklyn Atlantic Yards - Phase I [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	235,497
Initial Cost to Company, Land	554,855
Initial Cost to Company, Buildings and Improvements	0
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	554,855
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	0
Gross Amount at Which Carried at Close of January 31, 2013, Total	554,855
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Development Projects [Member] | Brooklyn Atlantic Yards - Phase II [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Brooklyn, NY
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	175,800
Initial Cost to Company, Buildings and Improvements	0
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	175,800
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	0
Gross Amount at Which Carried at Close of January 31, 2013, Total	175,800
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Development Projects [Member] | The Yards [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Washington, D.C.
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	0
Initial Cost to Company, Buildings and Improvements	59,326
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	0
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	59,326
Gross Amount at Which Carried at Close of January 31, 2013, Total	59,326
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Development Projects [Member] | Colorado Science + Technology Park at Fitzsimmons [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Aurora, CO
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	1,750
Initial Cost to Company, Buildings and Improvements	23,740
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,750
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	23,740
Gross Amount at Which Carried at Close of January 31, 2013, Total	25,490
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Development Projects [Member] | LiveWork Las Vegas [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Las Vegas, NV
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	141,853
Initial Cost to Company, Buildings and Improvements	0
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	141,853
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	0
Gross Amount at Which Carried at Close of January 31, 2013, Total	141,853
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Development Projects [Member] | The Science + Technology Park at Johns Hopkins [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Baltimore, MD
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	5,386
Initial Cost to Company, Buildings and Improvements	18,737
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	5,386
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	18,737
Gross Amount at Which Carried at Close of January 31, 2013, Total	24,123
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Development Projects [Member] | Waterfront Station [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Washington, D.C.
Amount of Encumbrance at January 31,2013	0
Initial Cost to Company, Land	559
Initial Cost to Company, Buildings and Improvements	28,107
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	559
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	28,107
Gross Amount at Which Carried at Close of January 31, 2013, Total	28,666
Accumulated Depreciation at January 31, 2013	0
Date of Construction/Acquisition Miscellaneous	Various
Construction and Development [Member]
Real Estate and Accumulated Depreciation [Line Items]
Amount of Encumbrance at January 31,2013	415,790
Initial Cost to Company, Land	982,000
Initial Cost to Company, Buildings and Improvements	344,703
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	982,000
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	344,703
Gross Amount at Which Carried at Close of January 31, 2013, Total	1,326,703
Accumulated Depreciation at January 31, 2013	0
Real Estate [Member]
Real Estate and Accumulated Depreciation [Line Items]
Amount of Encumbrance at January 31,2013	5,738,960
Initial Cost to Company, Land	1,746,727
Initial Cost to Company, Buildings and Improvements	6,841,409
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	1,435,168
Gross Amount at Which Carried at Close of January 31, 2013, Land	1,934,943
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	8,088,361
Gross Amount at Which Carried at Close of January 31, 2013, Total	10,023,304
Accumulated Depreciation at January 31, 2013	1,654,632
Land held for divestiture [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real estate and accumulated depreciation geographical location	Various
Amount of Encumbrance at January 31,2013	1,700
Initial Cost to Company, Land	2,706
Initial Cost to Company, Buildings and Improvements	0
Cost Capitalized Subsequent to Acquisition, Improvements and Carrying Costs	0
Gross Amount at Which Carried at Close of January 31, 2013, Land	2,706
Gross Amount at Which Carried at Close of January 31, 2013, Buildings and Improvements	0
Gross Amount at Which Carried at Close of January 31, 2013, Total	2,706
Accumulated Depreciation at January 31, 2013	$ 0