Stockholders' Equity - Stock Options (Narrative) (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Aecsoft
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense related to earn-out arrangement		$ 244
Spend Radar
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense related to earn-out arrangement		313
Common stock options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate intrinsic value of options exercised	831	1,098
Unrecognized compensation cost	14,373
Weighted average period over which unrecognized compensation cost is expected to be recognized	3 years 1 month 6 days
Stock-based compensation expense	1,238	789
Weighted average grant date fair value per share for stock options granted	$ 12.20	$ 8.62
Aggregate fair value of stock options vested	$ 971	$ 796

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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Amount of expense recognized from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments), awarded to key employees or individuals. Excludes amount related to plans that cover generally all employees (for example, but not limited to, qualified pension plans).

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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