Income Taxes (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2012	Dec. 31, 2011
Activity related to gross unrecognized tax benefit:
Balance at January 1		$ 11,860,000	$ 11,860,000
Additions based on tax positions related to the current year	11,860,000
Balance at December 31	11,860,000	11,860,000	11,860,000
Federal
Carryforwards
Net operating loss carryforwards		312,500,000
Portion of operating loss carryforward related to stock option deduction, which will be charged to additional paid-in capital when realized		116,900,000
Tax credit carryforwards		100,200,000
State
Carryforwards
Net operating loss carryforwards		437,600,000
Portion of operating loss carryforward related to stock option deduction, which will be charged to additional paid-in capital when realized		40,300,000
Tax credit carryforwards		$ 11,000,000