STOCK-BASED COMPENSATION - Restricted Stock - Additional Information (Detail) - Omnibus Plan [Member] - Restricted Stock [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted shares restricted stocks	911,470
Stock-based compensation expense	$ 3.2	$ 2.8	$ 3.4
Unrecognized compensation cost related to unvested shares	$ 3.2
Period for cost recognition not yet recognized	1 year 6 months
Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted shares restricted stocks	59,797	51,841
Restricted stock vesting period	1 year	1 year
Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted shares restricted stocks	851,673	262,371
Retirement Eligible Shares	47,194	16,808
Restricted stock vesting after two-year anniversary of the grant date [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-year anniversary of the grant date [Member] \| Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock vesting percentage	50.00%	50.00%

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement.

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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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