Consolidated Statement of Stockholders' Equity (Deficit) (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012
Statement of Stockholders' Equity [Abstract]
Issuance costs of common stock from July 2012 offering		$ 3,328
Issuance costs of common stock from November 2013 offering	4,529
Issuance costs of controlled equity offering	$ 371

Issuance Costs Of Common Stock From Additional Offering

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration