Derivatives	9 Months Ended
Sep. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	Derivatives As of September 30, 2018, we had an open position of 3,090 tonnes related to LME forward financial sales contracts, all of which are with Glencore, to fix the forward LME price. These contracts are expected to settle monthly, between November 1, 2019 and December 31, 2020. During the quarter ended September 30, 2018, we also entered into Midwest Premium ("MWP") forward financial sales contracts to fix the forward MWP. These contracts are expected to settle monthly through December 2019. As of September 30, 2018, we had an open position of 35,250 tonnes. We have financial contracts with various counterparties, including Glencore, to offset fixed price sales arrangements with certain of our customers (the “fixed for floating swaps”) to remain exposed to the LME price. As of September 30, 2018, we had open positions related to such arrangements of 9,255 tonnes settling at various dates through November 2019. In 2017, we entered into financial contracts to fix the forward price of approximately 4% of Grundartangi's total power requirements for the period November 1, 2019 through December 31, 2020 (the “power price swaps”). As of September 30, 2018, we had an open position of 256,200 MWh related to the power price swaps. Because the power price swaps are settled in euros, in 2018 we entered into financial contracts to hedge the risk of fluctuations associated with the euro (the "fx swaps"). As of September 30, 2018, we had open positions related to the fx swaps for €2.8 million euros that settle monthly from November 1, 2019 through December 31, 2020. As of September 30, 2018, we had a derivative asset and liability of $3.3 million and $0.9 million, respectively, in the consolidated balance sheet. At December 31, 2017, we had a derivative asset and liability of $1.7 million and $1.2 million, respectively, in the consolidated balance sheets. For the three and nine months ended September 30, 2018, we recognized gains of $0.8 million and $2.8 million, respectively, related to our derivative instruments in the consolidated statements of operations, a portion of which related to transactions with Glencore. For the three months ended September 30, 2017, we recognized a loss of $3.9 million and for the nine months ended September 30, 2017, we recognized a loss of $17.1 million in the consolidated statements of operations, substantially all of which related to transactions with Glencore.

Derivatives

As of September 30, 2018, we had an open position of 3,090 tonnes related to LME forward financial sales contracts, all of which are with Glencore, to fix the forward LME price. These contracts are expected to settle monthly, between November 1, 2019 and December 31, 2020. During the quarter ended September 30, 2018, we also entered into Midwest Premium ("MWP") forward financial sales contracts to fix the forward MWP. These contracts are expected to settle monthly through December 2019. As of September 30, 2018, we had an open position of 35,250 tonnes.

We have financial contracts with various counterparties, including Glencore, to offset fixed price sales arrangements with certain of our customers (the “fixed for floating swaps”) to remain exposed to the LME price. As of September 30, 2018, we had open positions related to such arrangements of 9,255 tonnes settling at various dates through November 2019.

In 2017, we entered into financial contracts to fix the forward price of approximately 4% of Grundartangi's total power requirements for the period November 1, 2019 through December 31, 2020 (the “power price swaps”). As of September 30, 2018, we had an open position of 256,200 MWh related to the power price swaps. Because the power price swaps are settled in euros, in 2018 we entered into financial contracts to hedge the risk of fluctuations associated with the euro (the "fx swaps"). As of September 30, 2018, we had open positions related to the fx swaps for €2.8 million euros that settle monthly from November 1, 2019 through December 31, 2020.

As of September 30, 2018, we had a derivative asset and liability of $3.3 million and $0.9 million, respectively, in the consolidated balance sheet. At December 31, 2017, we had a derivative asset and liability of $1.7 million and $1.2 million, respectively, in the consolidated balance sheets.

For the three and nine months ended September 30, 2018, we recognized gains of $0.8 million and $2.8 million, respectively, related to our derivative instruments in the consolidated statements of operations, a portion of which related to transactions with Glencore. For the three months ended September 30, 2017, we recognized a loss of $3.9 million and for the nine months ended September 30, 2017, we recognized a loss of $17.1 million in the consolidated statements of operations, substantially all of which related to transactions with Glencore.