Stockholders' Equity - Stock Options Additional Disclosures (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Number of shares	122,821	258,539
Options Outstanding, Weighted-Average Remaining Life	3 years 9 months 15 days
Options Outstanding, Weighted-Average Exercise Price	$ 0.85
Options Exercisable, Number of Shares	113,688
Options Exercisable, Weighted-Average Exercisable Price	$ 0.34
Aggregate intrinsic value of the options exercised	$ 4,230	$ 2,380	$ 492
Total grant date fair value of stock options vested	$ 5	$ 6	$ 16
Exercise Price Range 0.00 - 0.04
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Exercise Price, maximum	$ 0.00
Exercise Price, minimum	$ 0.04
Number of shares	5,381
Options Outstanding, Weighted-Average Remaining Life	2 years 7 months 24 days
Options Outstanding, Weighted-Average Exercise Price	$ 0.04
Options Exercisable, Number of Shares	5,381
Options Exercisable, Weighted-Average Exercisable Price	$ 0.04
Exercise Price Range 0.06
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Exercise Price, maximum	$ 0.06
Exercise Price, minimum	$ 0.06
Number of shares	63,379
Options Outstanding, Weighted-Average Remaining Life	2 years 10 months 10 days
Options Outstanding, Weighted-Average Exercise Price	$ 0.06
Options Exercisable, Number of Shares	63,379
Options Exercisable, Weighted-Average Exercisable Price	$ 0.06
Exercise Price Range 0.10 - 0.18
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Exercise Price, maximum	$ 0.10
Exercise Price, minimum	$ 0.18
Number of shares	18,096
Options Outstanding, Weighted-Average Remaining Life	3 years 7 months 28 days
Options Outstanding, Weighted-Average Exercise Price	$ 0.15
Options Exercisable, Number of Shares	18,096
Options Exercisable, Weighted-Average Exercisable Price	$ 0.15
Exercise Price Range 0.29 - 0.33
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Exercise Price, maximum	$ 0.29
Exercise Price, minimum	$ 0.33
Number of shares	14,701
Options Outstanding, Weighted-Average Remaining Life	4 years 4 months 24 days
Options Outstanding, Weighted-Average Exercise Price	$ 0.31
Options Exercisable, Number of Shares	14,701
Options Exercisable, Weighted-Average Exercisable Price	$ 0.31
Exercise Price Range 1.78
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Exercise Price, maximum	$ 1.78
Exercise Price, minimum	$ 1.78
Number of shares	4,693
Options Outstanding, Weighted-Average Remaining Life	5 years 7 months 2 days
Options Outstanding, Weighted-Average Exercise Price	$ 1.78
Options Exercisable, Number of Shares	3,701
Options Exercisable, Weighted-Average Exercisable Price	$ 1.78
Exercise Price Range 1.85
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Exercise Price, maximum	$ 1.85
Exercise Price, minimum	$ 1.85
Number of shares	4,865
Options Outstanding, Weighted-Average Remaining Life	6 years 0 months 15 days
Options Outstanding, Weighted-Average Exercise Price	$ 1.85
Options Exercisable, Number of Shares	3,938
Options Exercisable, Weighted-Average Exercisable Price	$ 1.85
Exercise Price Range 2.95
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Exercise Price, maximum	$ 2.95
Exercise Price, minimum	$ 2.95
Number of shares	2,506
Options Outstanding, Weighted-Average Remaining Life	6 years 7 months 21 days
Options Outstanding, Weighted-Average Exercise Price	$ 2.95
Options Exercisable, Number of Shares	1,567
Options Exercisable, Weighted-Average Exercisable Price	$ 2.95
Exercise Price Range 3.23
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Exercise Price, maximum	$ 3.23
Exercise Price, minimum	$ 3.23
Number of shares	4,500
Options Outstanding, Weighted-Average Remaining Life	6 years 9 months 26 days
Options Outstanding, Weighted-Average Exercise Price	$ 3.23
Options Exercisable, Number of Shares	2,925
Options Exercisable, Weighted-Average Exercisable Price	$ 3.23
Exercise Price Range 10.39
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Exercise Price, maximum	$ 10.39
Exercise Price, minimum	$ 10.39
Number of shares	3,500
Options Outstanding, Weighted-Average Remaining Life	7 years 6 months 22 days
Options Outstanding, Weighted-Average Exercise Price	$ 10.39
Options Exercisable, Number of Shares	0
Options Exercisable, Weighted-Average Exercisable Price	$ 0.00
Exercise Price Range 15.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Exercise Price, maximum	$ 15.00
Exercise Price, minimum	$ 15.00
Number of shares	1,200
Options Outstanding, Weighted-Average Remaining Life	7 years 9 months 22 days
Options Outstanding, Weighted-Average Exercise Price	$ 15.00
Options Exercisable, Number of Shares	0
Options Exercisable, Weighted-Average Exercisable Price	$ 0.00