Capital Stock (Tables)

12 Months Ended

Dec. 31, 2011

Capital Stock

Schedule of common stock outstanding

(Number of shares in millions)	2011		2010	2009
Common stock:
Balance, beginning of year	99.5		98.6	98.3
Activity under stock plans	1.5		0.9	0.3
Balance, end of year	101.0		99.5	98.6
Treasury stock:
Balance, beginning of year	2.2		2.0	1.9
Issued under stock plans	(0.5	)	—	—
Repurchased	0.5		0.2	0.1
Balance, end of year	2.2		2.2	2.0
Common stock outstanding	98.8		97.3	96.6