Common Stock (Tables)

9 Months Ended

Sep. 30, 2012

Assumptions Used for Calculating Fair Values of Stock Option Awards

The fair value of share-based awards is determined at the time the awards are granted which is generally in January of each year, and requires judgment in estimating employee and market behavior.

	Nine Months  Ended September 30,
	2012			2011
Stock Options Granted
Weighted average grant date fair value, per share	$	17.35		$	26.13
Weighted average assumptions used:
Expected volatility		73.5	%		70.1	%
Expected lives		4.7			4.8
Risk-free interest rates		0.8	%		1.8	%
Dividend yields		0.0	%		0.0	%

Stock Options Status and Activity

Stock Options — The following table reflects the status and activity for all options to purchase common stock for the period indicated:

	Nine Months Ended September 30, 2012
	Shares Under Option			Weighted Avg. Exercise Prices		Weighted Avg. Remaining Life in Years		Aggregate Intrinsic Value
								(Millions)
Outstanding Stock Options
Outstanding, January 1, 2012		2,743,199		$	17.43		4.0	$	37
Granted		316,799			29.83
Canceled		(22,840	)		16.00
Forfeited		(15,206	)		16.68
Exercised		(104,742	)		13.99				2
Outstanding, March 31, 2012		2,917,210		$	18.92		4.2	$	51
Granted		8,729			38.52
Forfeited		(4,417	)		32.03
Exercised		(10,274	)		5.56				—
Outstanding, June 30, 2012		2,911,248		$	19.00		4.0	$	36
Granted		202			28.76
Forfeited		(15,602	)		25.54
Exercised		(117,242	)		12.75				2
Outstanding, September 30, 2012		2,778,606		$	19.23		3.9	$	31

Nonvested Restricted Shares

Restricted Stock — The following table reflects the status for all nonvested restricted shares for the period indicated:

	Nine Months Ended September 30, 2012
	Shares			Weighted Avg. Grant Date Fair Value
Nonvested Restricted Shares
Nonvested balance at January 1, 2012		407,751		$	22.64
Granted		217,225			29.83
Vested		(246,314	)		15.74
Forfeited		(2,378	)		9.71
Nonvested balance at March 31, 2012		376,284		$	31.39
Granted		5,974			38.52
Vested		(7,126	)		24.32
Forfeited		(2,491	)		31.79
Nonvested balance at June 30, 2012		372,641		$	31.64
Granted		125			28.76
Vested		(20,660	)		30.63
Forfeited		(3,161	)		32.12
Nonvested balance at September 30, 2012		348,945		$	31.69