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STOCK-BASED COMPENSATION PLANS - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost	$ 4,800,000	$ 4,800,000	$ 5,300,000
Total recognized tax benefit	$ 1,300,000	$ 1,300,000	$ 2,000,000.0
Weighted average fair value of stock awards granted (USD per share)	$ 29.47	$ 37.87	$ 35.84
Vesting period	5 years
Total fair value of awards vested	$ 4,800,000	$ 4,800,000	$ 4,400,000
Expected weighted-average period for recognition of unrecognized compensation	2 years
Unrecognized stock-based compensation expense	$ 8,500,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost	93,000	0	0
Total recognized tax benefit	$ 25,000	0	0
Vesting period	5 years
Contractual life	10 years
Weighted average remaining contractual term for options outstanding	2 years
Total intrinsic value	$ 149,000	855,000	363,000
Unrecognized stock-based compensation expense	$ 124,000	$ 0	$ 0
2018 Equity Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under the plan (shares)	1,000,000.0
Number of shares available for grant under the plan (shares)	1,100,000
2018 Equity Compensation Plan | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted against the share limit for each stock granted (percent)	300.00%
2018 Equity Compensation Plan | Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted against the share limit for each stock granted (percent)	100.00%

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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