EMPLOYEE BENEFIT PLANS Rollforward of Change in Benefit Obligation (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation (PBO) at beginning of period	$ 545,128	$ 517,186
Service cost	655	856	$ 627
Interest cost	12,984	12,914	15,330
Actuarial loss (gain)	9,702	(19,930)
Benefit payments and expenses	(28,593)	(27,002)
Plan amendments	3,020	0
Effect of exchange rate changes	(38,820)	61,104
Projected benefit obligation (PBO) at end of period	$ 504,076	$ 545,128	$ 517,186

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of foreign currency translation gain (loss) which (increases) decreases benefit obligation of defined benefit plan.

+ References

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of increase (decrease) in benefit obligation of defined benefit plan from change in terms of existing plan or initiation of new plan.

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Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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