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Amount of assets acquired at the acquisition date.

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

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

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-Topic 805

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Amount of liabilities assumed at 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 assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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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.

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Allocation of Purchase Price of Assets Acquired and Liabilities Assumed, Interclick (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2011 Interclick	Dec. 14, 2011 Interclick	Dec. 14, 2011 Interclick Customer Contracts and Related Relationships	Dec. 14, 2011 Interclick Developed Technology And Patents	Dec. 14, 2011 Interclick Trade Names, Trademarks, And Domain Names
Business Acquisition [Line Items]
Cash acquired					$ 4,369
Other tangible assets acquired					71,711
Amortizable intangible assets				79,000		42,700	35,600	600
Goodwill	4,679,648	3,826,749	3,900,752	171,641	171,641
Total assets acquired					326,621
Liabilities assumed					(68,120)
Total					$ 258,501