Non-Controlling Interest (Tables)

12 Months Ended

Dec. 31, 2011

Noncontrolling Interest [Abstract]

Redeemable Noncontrolling Interest

	Redemption Price		Shares Outstanding				December 31,
			2011		2010		2011		2010
							(millions of dollars)
4.0% Series of 1944, $100 per share par value	$	105.50		—		24,268	$	—	$	2
4.35% Series of 1949, $100 per share par value	$	101.00		—		2,942		—		—
4.35% Series of 1953, $100 per share par value	$	101.00		—		1,680		—		—
4.10% Series of 1954, $100 per share par value	$	101.00		—		20,504		—		2
4.75% Series of 1958, $100 per share par value	$	101.00		—		8,631		—		1
5.0% Series of 1960, $100 per share par value	$	100.00		—		4,120		—		1
Total Preferred Stock of Subsidiaries				—		62,145	$	—	$	6