Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jul. 31, 2011 Common Class A [Member]	Jan. 31, 2011 Common Class A [Member]	Jul. 31, 2011 Common Class B [Member]	Jan. 31, 2011 Common Class B [Member]	Jul. 31, 2011 Series A Preferred Stock [Member]	Jan. 31, 2011 Series A Preferred Stock [Member]	Jul. 31, 2011 Other Preferred Stock [Member]	Jan. 31, 2011 Other Preferred Stock [Member]	Jul. 31, 2011 Variable interest entities [Member]	Jan. 31, 2011 Variable interest entities [Member]
Real Estate
Real Estate, net									$ 1,855,700	$ 2,627,800
Cash and equivalents									20,000	24,700
Restricted cash and escrowed funds									292,700	471,400
Other Assets									136,900	166,800
Liabilities
Mortgage debt and notes payable, nonrecourse									956,600	1,879,000
Senior and subordinated debt									29,000	29,000
Accounts payable and accrued expenses									$ 142,600	$ 150,200
Shareholders' Equity
Preferred Stock, without par value
Preferred stock, liquidation Preference					$ 50	$ 50
Preferred stock, shares authorized					6,400,000	6,400,000	13,600,000	13,600,000
Preferred stock, shares issued					4,399,998	4,399,998
Preferred stock, shares outstanding					4,399,998	4,399,998
Preferred stock dividend rate					7.00%	7.00%
Common stock - $.33 1/3 par value
Common stock, par value	$ 0.333	$ 0.333	$ 0.333	$ 0.333
Common stock, shares authorized	371,000,000	371,000,000	56,000,000	56,000,000
Common stock, shares issued	148,269,583	144,251,634	20,987,364	21,218,753
Common stock, shares outstanding	148,162,038	144,230,310	20,987,364	21,218,753
Common stock, shares issuable			26,257,961	26,257,961
Treasury stock, Class A Shares	107,545	21,324