Consolidated Statement of Changes in Stockholders' Equity (USD $) In Millions, unless otherwise specified		Total	Common stock	Treasury stock	Profit employed in the business	Accumulated other comprehensive income (loss)	Noncontrolling interests
Balance at Dec. 31, 2010		$ 10,864	$ 3,888	$ (10,397)	$ 21,384	$ (4,051)	$ 40
Increase (Decrease) in Stockholders' Equity
Profit of consolidated and affiliated companies		1,243			1,225		18
Foreign currency translation, net of tax		225				217	8
Pension and other postretirement benefits, net of tax		95				95
Derivative financial instruments, net of tax		10				10
Available-for-sale securities, net of tax		5				5
Common shares issued from treasury stock for stock-based compensation: 4,804,576 and 5,629,306 for the three months ended March 31, 2012 and 2011, respectively		58	(8)	66
Stock-based compensation expense		44	44
Net excess tax benefits from stock-based compensation		120	120
Cat Japan share redemption	[1]	8			31		(23)
Balance at Mar. 31, 2011		12,672	4,044	(10,331)	22,640	(3,724)	43
Balance at Dec. 31, 2011		12,929	4,273	(10,281)	25,219	(6,328)	46
Increase (Decrease) in Stockholders' Equity
Profit of consolidated and affiliated companies		1,611			1,586		25
Foreign currency translation, net of tax		181				195	(14)
Pension and other postretirement benefits, net of tax		113				110	3
Derivative financial instruments, net of tax		(28)				(28)
Available-for-sale securities, net of tax		19				18	1
Distribution to noncontrolling interests		(4)					(4)
Common shares issued from treasury stock for stock-based compensation: 4,804,576 and 5,629,306 for the three months ended March 31, 2012 and 2011, respectively		7	(110)	117
Stock-based compensation expense		47	47
Net excess tax benefits from stock-based compensation		141	141
Cat Japan share redemption	[1]				10		(10)
Balance at Mar. 31, 2012		$ 15,016	$ 4,351	$ (10,164)	$ 26,815	$ (6,033)	$ 47

[1] See Note 16 regarding the Cat Japan share redemption.