EMPLOYEE BENEFIT PLANS - Additional Information (Details) - United Kingdom - Pension Plan $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Weighted-average of expected returns on asset investment, percentage	2.10%
Expected contributions for current year	$ 4.1
Total contributions to date	$ 3.1
Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Weighted-average of expected returns on asset investment, percentage	1.40%
Defined Benefit Plan, Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Weighted-average of expected returns on asset investment, percentage	4.60%

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of contributions received and expected to be received by defined benefit plan from employer in current fiscal year.

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