Stockholders' Equity and Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2012

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Transactions under the stock option plans

Transactions under the stock option plans are summarized as follows:

	Option Price per Share	Outstanding		Vested		Available for Grant
January 1, 2010	$1.07-$16.39	7,766,188		5,042,682		410,873
Increase in shares authorized	—	—		—		2,500,000
Granted	3.42-7.19	1,249,900		—		(1,249,900	)
Vested	—	—		1,370,897		—
Exercised	1.07-7.31	(323,610	)	(323,610	)	—
Cancelled/forfeited	1.07-16.12	(970,686	)	(700,561	)	674,363
Restricted stock granted out of option plans	—	—		—		(762,680	)
Restricted stock forfeited or cancelled for employee minimum income taxes and returned to the plans	—	—		—		76,044
December 31, 2010	2.49-16.39	7,721,792		5,389,408		1,648,700
Increase in shares authorized	—	—		—		5,000,000
Granted	5.81-10.09	1,559,400		—		(1,559,400	)
Vested	—	—		851,222		—
Exercised	2.49-11.51	(2,145,792	)	(2,145,792	)	—
Cancelled/forfeited	3.00-15.43	(344,100	)	(250,300	)	262,513
Restricted stock granted out of option plans	—	—		—		(651,661	)
Restricted stock forfeited or cancelled for employee minimum income taxes and returned to the plans	—	—		—		93,488
December 31, 2011	2.49-16.39	6,791,300		3,844,538		4,793,640
Granted	5.96-7.16	1,544,000		—		(1,544,000	)
Vested	—	—		1,060,275		—
Exercised	2.49-7.76	(194,410	)	(194,410	)	—
Cancelled/forfeited	2.49-15.43	(212,540	)	(119,165	)	127,125
Restricted stock granted out of option plans	—	—		—		(667,000	)
Restricted stock forfeited or cancelled for employee minimum income taxes and returned to the plans	—	—		—		229,163
December 31, 2012	$2.80-$16.39	7,928,350		4,591,238		2,938,928

Summary of stock options outstanding

Stock options outstanding at December 31, 2012 are summarized as follows:

Option Price per Share	Outstanding	Weighted Average Exercise Price of Outstanding Options		Weighted Average Remaining Contract Life	Vested	Weighted Average  Exercise Price of Vested Options
$2.80 - $4.58	1,400,175	$	3.36	6.1	1,258,425	$	3.36
4.90 - 7.45	4,783,225	$	6.30	8.1	1,606,613	$	6.31
7.76 - 13.29	824,500	$	9.96	3.6	805,750	$	9.96
14.03 - 16.39	920,450	$	15.22	5.0	920,450	$	15.22
Totals	7,928,350	$	7.19	6.9	4,591,238	$	7.98

Additional Information related to the Company's stock options

Additional information related to the Company’s stock options is as follows:

	Number of Shares		Weighted Average Exercise Price		Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Life in Years	Aggregate Intrinsic Value (000’s)
Total outstanding at January 1, 2012	6,791,300		$	7.42			7.1
Options granted	1,544,000		$	6.05	$	3.54
Options exercised	(194,410	)	$	4.15
Options cancelled	(93,375	)	$	5.98
Options forfeited	(119,165	)	$	10.29
Total outstanding at December 31, 2012	7,928,350		$	7.19			6.9	$	6,510
Options exercisable and vested at December 31, 2012	4,591,238		$	7.98			5.4	$	4,664

Status of the Company's restricted stock and restricted stock unit awards

The status of the Company’s restricted stock and restricted stock unit awards for 2012 is as follows:

	Number of  Shares/Units
Total nonvested at January 1, 2012	1,154,795
Granted	667,000
Vested	(764,704	)
Forfeited	(23,644	)
Total nonvested at December 31, 2012	1,033,447

Assumptions used to calculate the fair value of option and SAR award on the grant date using the Black-Scholes option pricing model

The following assumptions were used for each respective period:

	Years Ended December 31,
	2012		2011		2010
Risk-free interest rates	0.7% – 1.0%		1.1% – 1.9%		1.5% – 2.5%
Expected lives (in years)	5.5		5.5		5.5
Expected dividend yield	—	%	—	%	—	%
Expected volatility	67.8% – 72.2%		65.9% – 80.2%		67.4% – 71.6%