RETIREMENT PLANS - Net Assets and Allocations (Details) - Pension Plans - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pension plan assets
Fair value of plan assets	$ 83,350	$ 77,530	$ 80,892
Weighted-average asset allocations (as a percent)	100.00%	100.00%
Level 1
Pension plan assets
Fair value of plan assets	$ 53,533	$ 29,858
Level 2
Pension plan assets
Fair value of plan assets	29,380	47,182
Level 3
Pension plan assets
Fair value of plan assets	437	490
Cash, cash equivalents, money markets and other
Pension plan assets
Fair value of plan assets	$ 4,982	$ 5,173
Weighted-average asset allocations (as a percent)	6.00%	7.00%
Cash, cash equivalents, money markets and other | Level 1
Pension plan assets
Fair value of plan assets	$ 4,982	$ 5,173
Common Stock
Pension plan assets
Fair value of plan assets	$ 26,702	$ 23,052
Weighted-average asset allocations (as a percent)	32.00%	30.00%
Common Stock | Level 1
Pension plan assets
Fair value of plan assets	$ 22,451	$ 18,760
Common Stock | Level 2
Pension plan assets
Fair value of plan assets	4,251	4,292
Mutual funds - fixed income
Pension plan assets
Fair value of plan assets	$ 12,970	$ 16,444
Weighted-average asset allocations (as a percent)	16.00%	21.00%
Mutual funds - fixed income | Level 1
Pension plan assets
Fair value of plan assets	$ 12,970
Mutual funds - fixed income | Level 2
Pension plan assets
Fair value of plan assets		$ 16,444
Mutual funds - equities
Pension plan assets
Fair value of plan assets	$ 10,921	$ 13,099
Weighted-average asset allocations (as a percent)	13.00%	17.00%
Mutual funds - equities | Level 1
Pension plan assets
Fair value of plan assets	$ 10,921	$ 4,748
Mutual funds - equities | Level 2
Pension plan assets
Fair value of plan assets		8,351
Fixed income securities
Pension plan assets
Fair value of plan assets	$ 26,307	$ 18,095
Weighted-average asset allocations (as a percent)	32.00%	23.00%
Fixed income securities | Level 1
Pension plan assets
Fair value of plan assets	$ 1,178
Fixed income securities | Level 2
Pension plan assets
Fair value of plan assets	25,129	$ 18,095
Other
Pension plan assets
Fair value of plan assets	$ 1,468	$ 1,667
Weighted-average asset allocations (as a percent)	1.00%	2.00%
Other | Level 1
Pension plan assets
Fair value of plan assets	$ 1,031	$ 1,177
Other | Level 3
Pension plan assets
Fair value of plan assets	$ 437	$ 490