Stock Options (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2013

Dec. 31, 2012

2008 Stock Incentive Plan

Stock Options

Schedule of assumptions used for the option grants

	Three months ended March 31, 2012
Option term (years)	6.380
Volatility	71.89		%
Risk-free interest rate	1.14 — 1.19		%
Dividend yield	0		%
Weighted-average grant date fair value per option granted	$	1.74

	Year Ended December 31,
	2012			2011			2010
Option term (years)		6.380			6.380			6.375
Volatility		71.89	%		67.15%–74.54	%		63.71%–67.88	%
Risk-free interest rate		1.14–1.43	%		1.15–2.62	%		1.57–3.06	%
Dividend yield		0	%		0	%		0	%
Weighted-average grant date fair value per option granted	$	1.73		$	1.74		$	3.46

Schedule of stock options

	Number of options		Weighted Average Exercise Price		Weighted Average Fair Value		Weighted Average Remaining Contractual Term (Years)
Outstanding at December 31, 2010		6,308	$	6.13		—		7.64
Granted		2,130		5.44	$	1.74
Exercised		—		—
Forfeited or modified		3,000		6.13
Outstanding at December 31, 2011		5,438	$	5.86		—		7.56
Granted		185		6.00	$	1.73
Exercised		—		—
Forfeited or modified		5,623		5.85
Outstanding at December 31, 2012		—	$	—				—

2012 Stock Incentive Plan

Stock Options

Schedule of assumptions used for the option grants

	Three months ended March 31,2013
Option term (years)	5.00
Volatility	44.35		%
Risk-free interest rate	0.88		%
Dividend yield	0		%
Weighted-average grant date fair value per option granted	$	70.87

	Year ended December 31, 2012
Option term (years)		4.11–5.00
Volatility		39.18–44.35	%
Risk-free interest rate		0.54–0.76	%
Dividend yield		0	%
Weighted-average grant date fair value per option granted	$	32.56

Schedule of stock options

	Number of options	Weighted Average Exercise Price		Weighted Average Fair Value		Weighted Average Remaining Contractual Term (Years)
Outstanding at December 31, 2012	74.3	$	425.00	—		6.82
Granted	0.8	425.00		$	70.87
Exercised	—	—
Forfeited	0.6	425.00
Outstanding at March 31, 2013	74.5	$	425.00			6.56

	Number of options		Weighted Average Exercise Price		Weighted Average Fair Value		Weighted Average Remaining Contractual Term (Years)
Outstanding at December 31, 2011		—	$	—		—		—
Granted		75.0		425.00	$	32.56
Exercised		—		—
Forfeited		0.3		—
Outstanding at December 31, 2012		74.7	$	425.00				6.82