EMPLOYEE BENEFIT PLANS - Pension Plans Narrative (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Sep. 30, 2018	Mar. 31, 2018
Defined Benefit Plan [Abstract]
Estimated cash contributions	$ 16.7
Cash contributions	$ 8.5
Weighted-average expected long-term rate of return on assets		3.60%

No definition available.

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- Definition

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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- Definition

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

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

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