v2.4.0.8

Summary of Cash, Cash Equivalents and Short-Term Investments (Parenthetical) (Detail) (USD $) In Thousands, unless otherwise specified | 9 Months Ended |
--- | --- | ---
Sep. 30, 2014 | Dec. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Unrealized loss | $ 51 | $ 2
Available for sale securities gross unrealized losses duration of loss | Greater than 12 months |
Federal and municipal obligations |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Unrealized loss | $ 18,900 | $ 18,100

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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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