Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Mar. 31, 2018
Accounts Payable And Accrued Liabilities Current [Abstract]
Payroll and Incentive Compensation	$ 21,199	$ 25,290
Benefits	13,076	13,785
Interest	3,852	3,852
Property Taxes	8,292	5,422
Power and Fuel	1,473	1,545
Litigation Settlements	345	45,098
Rail Freight	2,012
Legal	2,185	1,435
Sales and Use Tax	929	890
Other	8,860	8,553
Accrued Expenses, Total	$ 62,223	$ 105,870

Accrued litigation settlements current.

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Accrued rail freight current.

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Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for utilities, such as electrical power, heating oil, natural gas, and water. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying amount of reserve for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid within one year of the date of the statement of financial position.

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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Carrying value as of the balance sheet date of liabilities incurred through that date and payable for statutory sales and use taxes, including value added tax. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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