Derivative liability - warrants (restated) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Derivative liability - warrants	$ 1,461	$ 0	[1]
Derivative Liability, Fair Value, Gross Liability	1,461
Fair Value, Inputs, Level 1 [Member]
Derivative Liability, Fair Value, Gross Liability	0
Fair Value, Inputs, Level 2 [Member]
Derivative Liability, Fair Value, Gross Liability	0
Fair Value, Inputs, Level 3 [Member]
Derivative liability - warrants	$ 1,461

[1] Derived from audited financial information