STOCK-BASED COMPENSATION - Restricted Stock - Additional Information (Detail) - Omnibus Plan [Member] - Restricted Stock [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted shares of restricted stock	265,616
Share based compensation cost	$ 0.9	$ 1.1
Stock based compensation expense unrecognized related to nonvested shares of restricted stock	$ 4.1
Period for cost recognition not yet recognized	2 years
Independent directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted shares of restricted stock	3,745
Restricted stock vesting period	1 year
Management [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted shares of restricted stock	261,871	341,189
Retirement Eligible Shares	13,308	20,447
Restricted stock vesting after two years [Member] \| Management [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting percentage	50.00%	50.00%
Restricted stock vesting after three years [Member] \| Management [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting percentage	50.00%	50.00%

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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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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Percentage of vesting of share-based compensation awards.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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