Shareholders' Equity (Tables)

3 Months Ended

Mar. 31, 2012

Shareholders' Equity [Abstract]

Summary of shareholders' equity activity

							Noncontrolling
	Total			Company			interest in
	shareholders'			shareholders'			consolidated
Millions of dollars	equity			equity			subsidiaries
Balance at December 31, 2011	$	13,216		$	13,198		$	18
Transactions with shareholders		94			95			(1	)
Comprehensive income		637			634			3
Payments of dividends to shareholders		(83	)		(83	)		-
Balance at March 31, 2012	$	13,864		$	13,844		$	20

							Noncontrolling
	Total			Company			interest in
	shareholders'			shareholders'			consolidated
Millions of dollars	equity			equity			subsidiaries
Balance at December 31, 2010	$	10,387		$	10,373		$	14
Transactions with shareholders		122			120			2
Comprehensive income		513			513			-
Payments of dividends to shareholders		(82	)		(82	)		-
Balance at March 31, 2011	$	10,940		$	10,924		$	16