PARENT COMPANY CONDENSED FINANCIAL INFORMATION, Condensed Statements of Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011		Mar. 31, 2011		Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Revenue:
Agribusiness													$ 155		$ 152		$ 97
Real estate leasing													93		81		71
Real estate sales													14		14		16
Costs and Expenses:
Cost of agribusiness goods and services													131		150		130
Cost of real estate sales and leasing													67		60		54
Selling, general and administrative													154		158		154
Income tax benefit (expense)	0.8		10.6		15.1		5.8		13.1	15.5	13.1	3.0	32.0		45.0		5.0
Loss from Continuing Operations	3.7		18.4		24.1		8.7		18.8	25.7	22.1	2.8	55.0		69.0		7.0
Income from discontinued operations, net of income taxes (Note 2)	(2.1)	[1]	(9.7)	[1]	(5.4)	[1]	(3.5)	[1]	1.4	0	6.8	14.5	(21.0)		23.0		37.0
Net Income	1.6		8.7		18.7		5.2		20.2	25.7	28.9	17.3	34.0		92.0		44.0
Total comprehensive income													24	[2]	91	[2]	59	[2]
A&B (Parent Company) [Member]
Revenue:
Agribusiness													128		117		73
Real estate leasing													24		16		13
Real estate sales													15		2		8
Interest and other													3		6		2
Total revenue													170		141		96
Costs and Expenses:
Cost of agribusiness goods and services													113		114		109
Cost of real estate sales and leasing													21		11		9
Selling, general and administrative													21		24		21
Interest and other													16		16		16
Income tax benefit (expense)													2.0		(12.0)		(22.0)
Total costs and expenses													173		153		133
Loss from Continuing Operations													(3.0)		(12.0)		(37.0)
Income from discontinued operations, net of income taxes (Note 2)													2.0		24.0		11.0
Income (loss) Before Equity in Income of Subsidiaries Consolidated													(1)		12		(26)
Equity in Income from Continuing Operations of Subsidiaries Consolidated													58		81		44
Equity in Income from Discontinued Operations of Subsidiaries Consolidated													(23)		(1)		26
Net Income													34.0		92.0		44.0
Other Comprehensive Income (Loss), net of income taxes													(10)		(1)		15
Total comprehensive income													$ 24		$ 91		$ 59

[1] See Note 2 for discussion of discontinued operations.

[2] Net of ($10) million and $5 million for 2011, ($10) million and $6 million for 2010, and $5 million each in 2009 for deferred taxes related to net gain/prior service cost and amortization of net loss/prior service cost, respectively.