Maturity period for marketable securities classified as available-for-sale.

No definition available.

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- Definition

Maximum maturity period for highly liquid investments.

+ References

No definition available.

+ Details

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- Definition

Minimum percentage of probability of realizing the benefit upon ultimate settlement.

+ References

No definition available.

+ Details

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- Definition

Revenue Targets Measurement Interval Period.

+ References

No definition available.

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- Definition

Fair value, as of the acquisition date, of potential payments under the contingent consideration arrangement including cash and shares.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 65

-Subparagraph a, b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 29, 30, 41, 42, 64

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Balance Type:	credit
Period Type:	instant

- Definition

Amounts receivable from issuing a card to individuals or businesses that allows someone to make a purchase on borrowed money.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.8)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Percentage of revenue generated from a single external customer that accounts for 10 percent or more of an entity's revenues.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

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- Definition

The percentage of net product revenue to total net revenue from the sale of goods as of year end.

+ References

No definition available.

+ Details

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Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended						3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Mar. 31, 2013 SinglePlatform [Member]	Dec. 31, 2012 SinglePlatform [Member]	Jun. 12, 2012 SinglePlatform [Member]	Mar. 31, 2013 Software and Website Development Costs [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of revenue received from Company's email marketing product	85.00%	86.00%
Minimum percentage of revenue for significant customer	10.00%	10.00%
Estimated economic life of the developed technology related to acquisition of Single Platform							3 years
Cash and cash equivalents and short term investments maturity period	3 months
Credit card receivables	$ 2,949		$ 2,509
Maturity period for marketable securities classified as available-for-sale	1 year
Contingent consideration liability associated with acquisition	$ 0		$ 0	$ 0	$ 0	$ 12,152
Intervals period to be measured revenue targets	6 months
Minimum percentage of probability of realizing the benefit upon ultimate settlement	50.00%