Amount of cash paid to acquire the entity.

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The acquisition-date fair value of the equity interests of the acquirer, including the number of instruments or interests issued or issuable in consideration for the business combination.

+ References

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Fair value of noncash consideration given by the acquirer to acquire the entity. Does not include cash paid, the fair value of debt and securities issued and liabilities incurred to acquire the entity.

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Number of shares of equity interests issued or issuable to acquire entity.

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- Definition

The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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For an acquired entity, price of a single share of a number of saleable stocks of a company.

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No definition available.

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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-Glossary Investing Activities

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents investments accounted for under the equity method of accounting as of the balance sheet date.

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The fair value of assets acquired in noncash investing or financing activities.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Business Combinations Business Combinations - Additional Information (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	1 Months Ended						12 Months Ended								12 Months Ended		1 Months Ended			1 Months Ended
	Aug. 30, 2011	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011	Jan. 31, 2013 Other Intangible Assets [Member]	Jan. 31, 2012 Other Intangible Assets [Member]	Jan. 31, 2013 Other Intangible Assets [Member] Minimum [Member]	Jan. 31, 2012 Other Intangible Assets [Member] Minimum [Member]	Jan. 31, 2013 Other Intangible Assets [Member] Maximum [Member]	Jan. 31, 2012 Other Intangible Assets [Member] Maximum [Member]	Jan. 31, 2013 Purchased Technology [Member] Minimum [Member]	Jan. 31, 2013 Purchased Technology [Member] Maximum [Member]	Jan. 31, 2013 Purchased Technologies [Member]	Jan. 31, 2012 Purchased Technologies [Member]	Jan. 31, 2012 Purchased Technologies [Member] Minimum [Member]	Jan. 31, 2012 Purchased Technologies [Member] Maximum [Member]	Mar. 18, 2010 Valor [Member]	Jan. 31, 2011 Valor [Member]	Mar. 18, 2010 Valor [Member] Other Intangible Assets [Member]	Mar. 18, 2010 Valor [Member] Other Intangible Assets [Member] Minimum [Member]	Mar. 18, 2010 Valor [Member] Other Intangible Assets [Member] Maximum [Member]	Mar. 18, 2010 Valor [Member] Purchased Technologies [Member]
Business Acquisition [Line Items]
Fair Value of Assets Acquired	$ 8,900
Amortizable Intangible Assets		3,420	13,110	24,900	1,360	7,130							2,060	5,980				18,600	6,300			12,300
Finite-Lived Intangible Asset, Useful Life							1 year	3 years	5 years	5 years	3 years	4 years			3 years	4 years				1 year	4 years	3 years
Equity Interest Issued or Issuable, Number of Shares																	5,621
Cost of Acquired Entity, Cash Paid																	32,715
Cost of Acquired Entity, Equity Interests Issued and Issuable																	47,163
Share Price																	$ 8.39
Cost of Acquired Entity, Other Noncash Consideration																	7,025
Equity Method Investments, Fair Value Disclosure																	29,500
Cash Acquired from Acquisition																	$ 27,110