Benefit Plans - Stock Options Activity under Share-Based Payment Plans (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Options
Granted (in shares)		0
Employees And Non Employee Stock Option
Options
Outstanding, as of beginning of period (in shares)	338,481,000
Granted (in shares)	4,327,000
Exercised (in shares)	(2,230,000)
Forfeited, cancelled or expired (in shares)	(6,295,000)
Outstanding as of end of period (in shares)	334,283,000
Exercisable (in shares)	116,131,000
Weighted- Average Exercise Price Per Share
Outstanding as of beginning of period (in dollars per share)	$ 3.29
Granted (in dollars per share)	3.62
Exercised (in dollars per share)	1.80
Forfeited (in dollars per share)	4.72
Outstanding as of end of period (in dollars per share)	3.28
Exercisable (in dollars per share)	$ 2.43
Weighted- Average Remaining Contractual Term (Years)
Outstanding	7 years 4 months 21 days
Exercisable	5 years 6 months 7 days
Aggregate Intrinsic Value
Outstanding	$ 226,265
Exercisable	$ 176,113