XML 107 R119.htm IDEA: XBRL DOCUMENT v2.4.0.8
Commitments and contingencies Legal Contingencies (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 12 Months Ended
Dec. 31, 2013
Dec. 31, 2013
Logan Kruger [Member]
Dec. 31, 2013
Grundartangi Power Agreement [Member]
Loss Contingencies [Line Items]      
Loss Contingency, Damages Sought, Value   $ 20,000  
Litigation Settlement, Amount   8,700 1,470
Litigation Settlement, Expense $ 8,400 $ 8,400