Inventories - Components of Inventories (Details) - USD ($) $ in Thousands	Jul. 31, 2019	Jan. 31, 2019	Jul. 31, 2018
Inventory Net [Abstract]
Finished goods	$ 152,262	$ 123,947	$ 129,587
Component parts	45,918	39,752	39,880
Work-in-process	2,773	1,612	1,950
Inventories	$ 200,953	$ 165,311	$ 171,417

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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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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- Definition

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date for elements of machinery or equipment held for the purpose of replacing similar parts in the course of repair or maintenance.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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