Bonds interest rate assumption.

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- Definition

Convertible preferred stock redemption value.

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No definition available.

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- Definition

Embedded derivative liability measurement expected term.

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- Definition

Embedded derivative liability risk free interest rate.

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No definition available.

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- Definition

Embedded derivative liability volatility rate.

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No definition available.

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- Definition

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

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- Definition

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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Value of input used to measure embedded derivative liability.

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Maximum period of time the entity is hedging its exposure to variability in future cash flows for forecasted transactions, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes forecasted transactions related to payment of variable interest on existing financial instruments.

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- Definition

Description of the reasons for holding or issuing derivative instruments and nonderivative hedging instruments. Includes discussion of the objectives for holding or issuing derivative instruments, the context needed to understand those objectives, and the strategies for achieving those objectives. The description generally distinguishes between derivative and nonderivative instruments by the types of hedging relationships and between those instruments used for risk management purposes and those used for other purposes. Information about those instruments is disclosed in the context of each instrument's primary underlying risk exposure (for example, interest rate, credit, foreign exchange rate, interest rate and foreign exchange rate, or overall price).

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- Definition

Per share amount of par value or stated value of stock classified as temporary equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable.

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Amount to be paid per share that is classified as temporary equity by entity upon redemption. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Derivative Financial Instruments - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Derivative instruments objectives	We use derivatives to partially offset our exposure to foreign currency, interest rate, aluminum and other commodity price risk. We may enter into forward contracts, option contracts, swaps, collars or other derivative instruments to offset some of the risk on expected future cash flows and on certain existing assets and liabilities.
Maximum length of time, foreign currency cash flow hedge	48 months
Par or stated value per share	$ 0.01	$ 0.01	$ 0.01
Convertible Preferred Stock, Redemption Value	$ 300,000,000
Embedded derivative, volatility rate	68.00%
Embedded derivative, risk free interest rate	1.60%
Expected Dividend Rate [Member]
Derivatives, Fair Value [Line Items]
Dividend yield rate	0
Minimum [Member] \| Expected Term [Member]
Derivatives, Fair Value [Line Items]
Valuation scenario term	2 years 3 months
Maximum [Member] \| Expected Term [Member]
Derivatives, Fair Value [Line Items]
Valuation scenario term	5 years 11 months 15 days
Embedded derivative liability [Member]
Derivatives, Fair Value [Line Items]
Redemption per share	$ 56.32
Par or stated value per share	$ 19.05
Debt instrument face value	$ 150,000,000
Convertible Preferred Stock, Redemption Value	$ 300,000,000
Risky bond rate	20.00%