STOCK INCENTIVE PLANS - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares available under incentive compensation plans (in shares) \| shares	2,037,154
Unrecognized compensation expense	$ 11.0
Intrinsic value of outstanding and exercisable stock options	1.1
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	11.1
Amount subject to accelerated vesting under Incentive Compensation Plan	$ 0.6
Service-Based Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of units issued, years	3 years
Unrecognized compensation expense	$ 8.0

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

+ References

No definition available.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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