RETIREMENT BENEFIT PLANS - Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Actual contribution to defined benefit pension plans	$ 15
Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected future employer contributions, current fiscal year	15
Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected future employer contributions, current fiscal year	$ 25