Acquisitions of and Investments in Businesses and Technologies - Total purchase price allocated to the estimated fair values of assets acquired and liabilities assumed (Details) - USD ($)
$ in Thousands

Jan. 31, 2017

Jan. 31, 2016

Apr. 30, 2015

Jan. 31, 2015

Nov. 03, 2014

Jan. 31, 2014

Business Acquisition [Line Items]

Goodwill

$ 40,649

$ 40,672

$ 52,148

$ 22,274

Integra Plastics [Member]

Business Acquisition [Line Items]

Cash

$ 1,600

Accounts receivable

4,808

Inventory

7,575

Deferred income taxes

543

Other current assets

Property, plant and equipment, net

17,088

Goodwill

27,422

$ 27,422

Customer relationships and other definite-lived intangibles

10,200

Short-term and long-term debt

(11,341)

(4,084)

(5,573)

$ 48,262

Short-term and long-term debt: Business Combination debt assumed on acquisition date. Includes lines of credit, current and noncurrent debt to banks, debt to previous owners

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount, after allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences and carryforwards acquired at the acquisition date, classified as current.

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=73531372&loc=d3e2207-128464

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-Publisher FASB
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-Section 50
-Paragraph 1
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- Definition

The amount of inventory recognized as of the acquisition date.

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-Publisher FASB
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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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