STOCK INCENTIVE PLANS - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units issued (in shares)	958,720	713,998
Common stock shares available under incentive compensation plans (in shares)	2,333,089
Unrecognized compensation expense	$ 16,284
Intrinsic value of outstanding and exercisable stock options	$ 2,400
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units issued (in shares)	958,720	713,998
Unrecognized compensation expense	$ 16,300
Amount subject to accelerated vesting under Incentive Compensation Plan	$ 1,000
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	$ 10,770
Performance-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	$ 5,514
Performance-Based Units [Member] \| Performance Based Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units issued (in shares)	283,037	251,379
Performance-Based Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock percentage of number of units issued	0.00%
Performance-Based Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock percentage of number of units issued	175.00%
Return On Average Tangible Assets (ROATA) [Member] \| Performance-Based Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of units issued, years	3 years
Return On Average Tangible Assets (ROATA) [Member] \| Performance-Based Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock percentage of number of units issued	0.00%
Return On Average Tangible Assets (ROATA) [Member] \| Performance-Based Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock percentage of number of units issued	175.00%
Total Shareholder Return (TSR) [Member] \| Performance-Based Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock percentage of number of units issued	75.00%
Total Shareholder Return (TSR) [Member] \| Performance-Based Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock percentage of number of units issued	125.00%

Assumption of percentage of restricted stock units issued for calculations.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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- Definition

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

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- Definition

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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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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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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- Definition

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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