v3.20.4

EMPLOYEE BENEFIT PLANS Table 5 - Major Classes of Plan Assets Measured at Fair Value (Details) - Pension Plan [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 182,727	$ 159,036	$ 126,949
Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	77,870	66,299
Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	104,857	92,737
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash equivalent securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,125	160
Cash equivalent securities [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,125	160
Cash equivalent securities [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash equivalent securities [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. large cap equity fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	104,857	92,737
U.S. large cap equity fund [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. large cap equity fund [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	104,857	92,737
U.S. large cap equity fund [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International stock index fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	20,732	17,473
International stock index fund [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	20,732	17,473
International stock index fund [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International stock index fund [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Bond market index fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	55,013	48,666
Bond market index fund [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	55,013	48,666
Bond market index fund [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Bond market index fund [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0

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