STOCK-BASED COMPENSATION - Performance Units - Additional Information (Detail) - Omnibus Plan [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted performance units	268,709	582,193
Stock-based compensation expense	$ 1.7	$ 3.3
Performance Shares [member] \| Executives [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted performance units	304,408
Vesting period	3 years
Retirement Eligible Shares	29,171
Performance units program description	The performance units will vest based on the achievement of a pre-established tangible book value per share target as of December 31, 2020. All of the performance units will vest if performance is at the pre-established performance target level or above. However, the participants may vest on 50% of the awards to the extent that performance is below the target but at 80% of the pre-established performance target level (the 80% minimum threshold), which is measured based upon the growth in the tangible book value during the performance cycle. If performance is between the 80% minimum threshold and the pre-established performance target level, the participants will vest on a proportional amount. No performance units will vest if performance is below the 80% minimum threshold.
Stock-based compensation expense	$ 0.6
Unrecognized compensation cost related to non-vested shares	$ 1.3

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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Unrecognized cost of unvested share-based compensation awards.

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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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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

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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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