Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=96947427&loc=d3e1505-109256

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section 50
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Net Income Per Share - Reconciliation of Common Shares Used for Basic and Diluted Earnings Per Share (Detail) - Successor [Member] - shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted average number of common shares and potential dilutive shares used for diluted earnings per share	45,367,932	45,723,524	46,006,027
Weighted average number of common shares used for basic earnings per share	45,367,932	45,212,414	45,173,542
Warrant [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	4,053,670	0	0
Effect of potential dilutive shares:
Effect of potential dilutive shares	0	312,619
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	126,667	110,000	110,000
Effect of potential dilutive shares:
Effect of potential dilutive shares	0	447
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	68,654	0	0
Effect of potential dilutive shares:
Effect of potential dilutive shares	0	116,105
Performance Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	322,943	0	0
Effect of potential dilutive shares:
Effect of potential dilutive shares	0	81,939
Warrant [Member]
Effect of potential dilutive shares:
Effect of potential dilutive shares			5,313
Employee Stock Option [Member]
Effect of potential dilutive shares:
Effect of potential dilutive shares			809,834
Performance Shares [Member]
Effect of potential dilutive shares:
Effect of potential dilutive shares			3,117
Restricted Stock Units (RSUs) [Member]
Effect of potential dilutive shares:
Effect of potential dilutive shares			14,221