Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Mar. 31, 2018
Summary of inventories
Raw materials	$ 38,331	$ 36,124
Work in process	13,240	13,670
Finished goods and other	58,866	59,358
Total Inventories	$ 110,437	$ 109,152

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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