Number of shares issued during the period as a result of the conversion of convertible securities.

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Name:	us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

EARNINGS (LOSS) PER COMMON SHARE - Computation of Basic and Diluted Net Income (Loss) Per Share (Parenthetical) (Detail) - shares shares in Thousands		3 Months Ended		9 Months Ended
	Sep. 14, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Antidilutive shares excluded from computation of diluted earnings per share
Number of shares representing the weighted impact of Series A conversion	4,700
Series A Mandatory Convertible Preferred Stock
Antidilutive shares excluded from computation of diluted earnings per share
Antidilutive shares excluded from computation of diluted earnings per share (in shares)		3,918	5,049	4,526	5,152
Number of shares representing the weighted impact of Series A conversion		800		300