Stock-Based Compensation

6 Months Ended

Jun. 30, 2011

Stock-Based Compensation [Abstract]

Stock-Based Compensation

8. Stock-Based Compensation

We issue stock-based incentive awards to our eligible employees and Directors under two employee stock ownership plans (the 1993 and 2002 Employee Stock Incentive Plans) and a Director Deferred Stock Ownership Plan. No further awards may be granted under the 1993 Plan, although awards granted under this plan remain outstanding in accordance with their terms. The 2002 Employee Stock Incentive Plan permits the granting of nonqualified stock options, stock appreciation rights, performance stock, restricted stock and other stock-based awards.

Stock-based compensation for the periods ended June 30 is as follows:

	Three Months				Six Months
	2011		2010		2011		2010
Stock option expense	$	6.2	$	6.0	$	11.8	$	10.3
Restricted stock and unit awards expense		16.9		8.6		29.4		12.7
Total stock-based compensation expense	$	23.1	$	14.6	$	41.2	$	23.0

As of June 30, 2011 and December 31, 2010, we issued 2.6 million and 1.8 million common shares, respectively, upon exercise of certain stock options outstanding.