Class A Common Units (Detail Textual) (USD $)	12 Months Ended
	Jan. 31, 2009 Project	Jan. 31, 2012 Common Class A [Member]	Jan. 31, 2011 Common Class A [Member]	Jan. 31, 2010 Common Class A [Member] Property	Nov. 08, 2006 Common Class A [Member] Property
Number of retail office residential properties and certain service companies					30
Class A Common Units Outstanding		3,646,755	3,646,755
Carrying Value of common units included as noncontrolling interest		$ 186,021,000	$ 186,021,000
Operating properties sold				1
Payment for tax indemnification in accordance with terms of the Tax Protection Agreement		1,074,000	1,695,000
Cost of interest transferred to affiliates of the company	121,000,000
Cost of interest transferred to affiliates of the company, payment period	15 years
Initial cash received by BCR entities	49,249,000
Initial discount amount	$ 56,495,000
Number of development projects	2