EMPLOYEE BENEFIT PLANS Reconciliation of Funded Status (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Retirement Benefits [Abstract]
Accumulated benefit obligation (ABO)	$ 545,128	$ 517,186
Projected benefit obligation (PBO)	545,128	517,186	$ 525,053
Fair value of assets	(508,375)	(455,539)	$ (454,946)
Net recognized pension liability	36,753	61,647
Amounts recognized in accumulated other comprehensive loss	$ 232,043	$ 220,396

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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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