EMPLOYEE BENEFIT PLANS (Fair Value of Assets of the Company's Qualified Plan) (Details) - Pension Benefits [Member] - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	$ 255.8	$ 197.4	$ 143.4
Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	255.8	197.4
Level 1 [Member] | Domestic Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	64.4	47.8
Level 1 [Member] | Developed International Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	38.2	29.5
Level 1 [Member] | Emerging Market Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	20.7	14.9
Level 1 [Member] | Global Low Volatility Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	22.5	16.9
Level 1 [Member] | Fixed-Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	95.7	74.9
Level 1 [Member] | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	13.3	8.3
Level 1 [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	$ 1.0	$ 5.1