Acquisitions of and Investments in Businesses and Technologies - Total purchase price allocated to the estimated fair values of assets acquired and liabilities assumed (Details) (Vista Research [Member], USD $) In Thousands, unless otherwise specified	Jan. 31, 2012
Business Acquisition [Line Items]
Cash	$ 320
Accounts receivable	2,375
Inventory	264
Other current and long term assets	3,342
Property, plant, and equipment, net	834
Goodwill	11,497
Current liabilities	(3,023)
Other liabilities	(150)
Existing Technology [Member]
Business Acquisition [Line Items]
Finite-lived intangibles	4,300
Total purchase price	23,269
Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-lived intangibles	3,260
Other Intangibles [Member]
Business Acquisition [Line Items]
Finite-lived intangibles	$ 250

Acquisitions of and Investments in Businesses and Technologies - Total purchase price allocated to the estimated fair values of assets acquired and liabilities assumed (Details) (Vista Research [Member], USD $)
In Thousands, unless otherwise specified

Jan. 31, 2012

$ 320

Accounts receivable

2,375

Inventory

264

Other current and long term assets

3,342

Property, plant, and equipment, net

834

Goodwill

11,497

Current liabilities

(3,023)

Other liabilities

(150)

Existing Technology [Member]

Business Acquisition [Line Items]

Finite-lived intangibles

4,300

Total purchase price

23,269

Customer Relationships [Member]

Business Acquisition [Line Items]

Finite-lived intangibles

3,260

Other Intangibles [Member]

Business Acquisition [Line Items]

Finite-lived intangibles

$ 250

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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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- Definition

Amount of 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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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 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6910749&loc=d3e4845-128472

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 55

-Paragraph 37

-URI http://asc.fasb.org/extlink&oid=25498275&loc=d3e2207-128464

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The amount of inventory recognized as of the acquisition date.

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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 recognized as of the acquisition date for the assets, including goodwill, in excess of (less than) the aggregate liabilities assumed, less the noncontrolling interest in the acquiree.

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