Debt Instrument, Convertible, Threshold Consecutive Trading Days, Term

No definition available.

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- Definition

Debt Instrument, Convertible, Threshold Trading Days, Term

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Interest Rate, Stated Percentage, Cash

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Payment Terms, Number of Monthly Payments

+ References

No definition available.

+ Details

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- Definition

Debt Instrument Redemption Period

+ References

No definition available.

+ Details

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- Definition

Debt Offer To Purchase Percentage Of Outstanding Amount

+ References

No definition available.

+ Details

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- Definition

The amount of additional borrowings provided in credit facility under a letter of credit sub-facility.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Option Indexed to Issuers' Equity, Cap Price

+ References

No definition available.

+ Details

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- Definition

Option Indexed to Issuer's Equity, Issuance Cost

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Write off of Deferred Financing Cost

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Percentage of principal amount of debt redeemed.

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No definition available.

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

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No definition available.

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Amount, after accumulated amortization, of debt discount.

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Amount of decrease in the fair value of derivatives recognized in the income statement.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Exercise or strike price stated in the contract for options indexed to the issuer's equity shares.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share.

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No definition available.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Debt - Narrative (Details)						1 Months Ended	3 Months Ended		6 Months Ended
Debt - Narrative (Details)	May 14, 2021	Apr. 14, 2021 USD ($)	Apr. 09, 2021 USD ($) $ / shares	Apr. 07, 2021 USD ($) $ / shares	Apr. 29, 2019 USD ($) payment	Apr. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Line of Credit Facility [Line Items]
Proceeds from issuance of debt									$ 250,000,000.0	$ 0
Loss on early extinguishment of debt							$ (24,700,000)	$ 0	(24,700,000)	0
Proceeds from convertible notes									$ 86,300,000	$ 0
Senior notes [Member]
Line of Credit Facility [Line Items]
Loss on early extinguishment of debt						$ 24,700,000
Redemption premium						18,100,000
Write off of deferred financing cost						4,400,000
Debt discount						2,200,000
Senior secured notes, 7.5% [Member] \| Senior notes [Member]
Line of Credit Facility [Line Items]
Stated interest rate, percentage		7.50%					7.50%		7.50%
Face amount		$ 250,000,000.0
Proceeds from issuance of debt		$ 245,200,000
Redemption price, percentage									100.00%
Redemption period									12 months
Percentage of outstanding amount, offer to purchase							101.00%		101.00%
Senior secured notes, 7.5% [Member] \| Senior notes [Member] \| Level 2 [Member]
Line of Credit Facility [Line Items]
Fair value of debt instrument							$ 265,400,000		$ 265,400,000
Senior secured notes, 12.0% [Member] \| Senior notes [Member]
Line of Credit Facility [Line Items]
Stated interest rate, percentage							12.00%		12.00%
Redemption price, percentage	107.00%
Debt instrument, repurchased face amount						$ 195,900,000
Debt discount							$ 2,300,000		$ 2,300,000
Convertible senior note [Member] \| Call Option [Member]
Line of Credit Facility [Line Items]
Issuance cost				$ 5,700,000
Strike price (in dollars per share) \| $ / shares				$ 18.74
Cap price (in dollars per share) \| $ / shares				$ 22.95
Loss on derivative				$ 1,000,000.0
Convertible senior note [Member] \| Senior notes [Member]
Line of Credit Facility [Line Items]
Face amount			$ 86,300,000
Percentage of principal amount redeemed			100.00%						100.00%
Proceeds from convertible notes			$ 83,700,000
Conversion ratio (in shares)			53.3547
Conversion price (in dollars per share) \| $ / shares			$ 18.74
Interest rate, cash percentage			2.75%
Threshold percentage of stock price trigger									130.00%
Threshold trading days									20 days
Consecutive trading days									30 days
Convertible senior note [Member] \| Senior notes [Member] \| Level 2 [Member]
Line of Credit Facility [Line Items]
Fair value of debt instrument							$ 83,500,000		$ 83,500,000
Revolving credit facility [Member]
Line of Credit Facility [Line Items]
Stated interest rate, percentage							5.375%		5.375%
Revolving credit facility [Member] \| U.S. revolving credit facility [Member]
Line of Credit Facility [Line Items]
Stated interest rate, percentage							3.75%		3.75%
Credit facility face amount							$ 175,000,000.0		$ 175,000,000.0
Outstanding borrowings							39,600,000		39,600,000
Credit facility maximum amount							175,000,000.0		175,000,000.0
Revolving credit facility [Member] \| U.S. letter of credit [Member]
Line of Credit Facility [Line Items]
Letter of credit sub-facility amount							110,000,000.0		110,000,000.0
Revolving credit facility [Member] \| U.S. revolving credit facility, accordion [Member]
Line of Credit Facility [Line Items]
Credit facility face amount							50,000,000.0		50,000,000.0
Revolving credit facility [Member] \| Iceland revolving line of credit [Member]
Line of Credit Facility [Line Items]
Outstanding borrowings							0		0
Credit facility maximum amount							50,000,000.0		50,000,000.0
Revolving credit facility							$ 0		$ 0		$ 45,000,000.0
Hawesville [Member]
Line of Credit Facility [Line Items]
Due to related parties, noncurrent					$ 40,000,000.0
Debt instrument, payment terms, number of monthly payments \| payment					24
London Interbank Offered Rate (LIBOR) [Member] \| Hawesville [Member]
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate					5.375%