Long-Term Debt - Current Classification of Convertible Notes (Details) - Convertible Notes - 7.875 percent convertible notes due 2026	6 Months Ended
Mar. 31, 2020 USD ($) trading_day $ / shares
Debt Instrument [Line Items]
Interest rate (percent)	7.875%
Trading days	20
Consecutive trading days	30
Threshold percentage of stock price trigger (greater than)	120.00%
Redemption Period One
Debt Instrument [Line Items]
Conversion ratio of common stock per principal	83.3333
Principal amount per note for conversion \| $	$ 1,000
Conversion price (in usd per share) \| $ / shares	$ 12.00

Debt Instrument, Convertible, Principal Amount Per Note For Conversion

No definition available.

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- Definition

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

+ References

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-Topic 470
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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

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

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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

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

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- Definition

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

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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.

+ References

No definition available.

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