Antidilutive securities contingently convertible shares excluded from computation of earnings per share amount.

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- Definition

Antidilutive securities excluded from computation of earnings per share weighted average exercise price.

+ References

No definition available.

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- Definition

Antidilutive securities excluded from computation of earnings per unit weighted average grant date fair value price.

+ References

No definition available.

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- Definition

Antidilutive securities performance share units excluded from computation of earnings per share amount.

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No definition available.

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- Definition

Antidilutive securities warrants for common stock, excluded from computation of earnings per share amount.

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No definition available.

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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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Summary of Significant Accounting Policies - Common Stock and Convertible Stock Dilutive in Computation of Earning Per Share (Detail) shares in Thousands, EquityUnit in Thousands	1 Months Ended	2 Months Ended	3 Months Ended	7 Months Ended	9 Months Ended
	Aug. 13, 2018 EquityUnit $ / shares $ / EquityUnit shares	Sep. 30, 2018 EquityUnit $ / shares $ / EquityUnit shares	Sep. 30, 2017 EquityUnit $ / shares $ / EquityUnit shares	Aug. 13, 2018 EquityUnit $ / shares $ / EquityUnit shares	Sep. 30, 2017 EquityUnit $ / shares $ / EquityUnit shares
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Weighted average warrants for common stock \| shares		15
Weighted average PSUs \| EquityUnit		315
Weighted average grant date fair value per unit \| $ / EquityUnit		12.93
Predecessor
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Weighted average warrants for common stock \| shares	42		415	142	479
Weighted average PSUs \| EquityUnit	514		303	476	281
Weighted average grant date fair value per unit \| $ / EquityUnit	13.83		17.12	13.83	17.12
Weighted average contingently convertible shares \| shares	40,631		37,624	39,819	36,676
Warrants for Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Weighted average exercise price per share \| $ / shares		$ 0.01
Warrants for Common Stock \| Predecessor
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Weighted average exercise price per share \| $ / shares	$ 0.01		$ 0.01	$ 0.01	$ 0.01
Contingently Convertible Shares \| Predecessor
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Weighted average exercise price per share \| $ / shares	$ 12.32		$ 12.32	$ 12.32	$ 12.32