v2.4.0.8

Summary of Cash, Cash Equivalents and Short-Term Investments (Detail) (USD $) In Thousands, unless otherwise specified | Sep. 30, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Dec. 31, 2012
--- | --- | --- | --- | ---
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Cost | $ 23,406 |  | $ 41,750 |  | $ 40,202 | $ 37,483
Cash and cash equivalents, Gross Unrealized Gains |  |  |  |  |  |
Short-term investment, Gross Unrealized Gains | 8 |  |  |  |  |
Gross Unrealized Gains | 8 |  |  |  |  |
Cash and Cash equivalent, Gross Unrealized Losses |  |  |  |  |  |
Short-term investment, Gross Unrealized (Losses) | (51) |  | (2) |  |  |
Gross Unrealized Losses | (51) |  | (2) |  |  |
Cash |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Gross Unrealized Gains |  |  |  |  |  |
Cash and Cash equivalent, Gross Unrealized Losses |  |  |  |  |  |
Term deposits |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Gross Unrealized Gains |  |  |  |  |  |
Cash and Cash equivalent, Gross Unrealized Losses |  |  |  |  |  |
Money market funds |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Gross Unrealized Gains |  |  |  |  |  |
Cash and Cash equivalent, Gross Unrealized Losses |  |  |  |  |  |
Federal and municipal obligations |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Gross Unrealized Gains |  |  |  |  |  |
Cash and Cash equivalent, Gross Unrealized Losses |  |  |  |  |  |
Short-term investment, Gross Unrealized (Losses) | (18,900) |  | (18,100) |  |  |
Corporate bonds |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Short-term investment, Gross Unrealized Gains | 8 | [1] |  |  |  |
Short-term investment, Gross Unrealized (Losses) | (51) | [1] | (2) | [2] |  |
Estimated Fair Value |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Short-term investment, Cost | 34,930 |  | 38,150 |  |  |
Total | 58,336 |  | 79,900 |  |  |
Cash and cash equivalents, Estimated Fair Value | 23,406 |  | 41,750 |  |  |
Estimated Fair Value | Cash |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Estimated Fair Value | 20,697 |  | 25,540 |  |  |
Estimated Fair Value | Term deposits |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Estimated Fair Value |  |  | 7,122 |  |  |
Estimated Fair Value | Money market funds |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Estimated Fair Value | 2,709 |  | 6,088 |  |  |
Estimated Fair Value | Federal and municipal obligations |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Short-term investment, Cost |  |  | 1,000 |  |  |
Cash and cash equivalents, Estimated Fair Value |  |  | 3,000 |  |  |
Estimated Fair Value | Commercial paper |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Short-term investment, Cost |  |  | 4,498 | [2] |  |
Estimated Fair Value | Corporate bonds |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Short-term investment, Cost | 34,930 | [1] | 32,652 | [2] |  |
Cost |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Cost | 23,406 |  | 41,750 |  |  |
Short-term investment, Cost | 34,973 |  | 38,152 |  |  |
Total | 58,379 |  | 79,902 |  |  |
Cost | Cash |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Cost | 20,697 |  | 25,540 |  |  |
Cost | Term deposits |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Cost |  |  | 7,122 |  |  |
Cost | Money market funds |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Cost | 2,709 |  | 6,088 |  |  |
Cost | Federal and municipal obligations |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Cash and cash equivalents, Cost |  |  | 3,000 |  |  |
Short-term investment, Cost |  |  | 1,000 |  |  |
Cost | Commercial paper |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Short-term investment, Cost |  |  | 4,498 | [2] |  |
Cost | Corporate bonds |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Short-term investment, Cost | $ 34,973 | [1] | $ 32,654 | [2] |  |
[1] | Securities totaling approximately $18.9 million were in an unrealized loss position at September 30, 2014. None of these securities were in a continuous unrealized loss position for greater than 12 months.
[2] | Securities totaling approximately $18.1 million were in an unrealized loss position at December 31, 2013. None of these securities were in a continuous unrealized loss position for greater than 12 months.

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