Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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Number of shares that have been repurchased during the period and are being held in treasury.

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STOCK-BASED COMPENSATION - Salary Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchased of common stock			433,362	336,985
Omnibus Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-Average Grant Date Fair Value of Stocks			$ 6.71
Omnibus Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation cost	$ 0.8	$ 1.0	$ 2.7	$ 3.0
Repurchased of common stock			336,985	243,102
Omnibus Plan [Member] \| Senior Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted shares			268,709	427,940
Weighted-Average Grant Date Fair Value of Stocks			$ 6.51	$ 5.88
Share based compensation cost			$ 1.7	$ 2.5
Omnibus Plan [Member] \| Senior Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchased of common stock			96,377	143,509