CONSOLIDATED STATEMENTS OF CASH FLOWS Non-Cash Activities (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Other Significant Noncash Transactions [Line Items]
Unrealized loss on available-for-sale securities	$ 43	$ (3)
Common Stock Issued To Board Of Directors And Scientific Advisory Board That Was Earned In Previous Period [Member]
Other Significant Noncash Transactions [Line Items]
Other Significant Noncash Transaction, Value of Consideration Received	323	300
Common Stock Issued To Employees That Was Accrued For In Previous Period Net Of Shares Withheld For Taxes [Member]
Other Significant Noncash Transactions [Line Items]
Other Significant Noncash Transaction, Value of Consideration Received	475	282
Other Capitalized Property Plant and Equipment [Member]
Other Significant Noncash Transactions [Line Items]
Other Significant Noncash Transaction, Value of Consideration Received	$ (305)	$ 909