v2.4.0.8

Short-term and Long-term Investments - Summary of Amortized Cost, Gross Unrealized Gains and Losses and Fair Value of Short-term Investments (Detail) (USD $) In Thousands, unless otherwise specified | Sep. 30, 2013
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Schedule of Available-for-sale Securities [Line Items] |
Amortized Cost | $ 217,757
Gross Unrealized Gains | 33
Gross Unrealized Losses | (9)
Aggregate Fair Value | 217,781
U.S. Government Debt Securities [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Amortized Cost | 205,747
Gross Unrealized Gains | 27
Gross Unrealized Losses | (6)
Aggregate Fair Value | 205,768
Commercial Paper [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Amortized Cost | 10,242
Gross Unrealized Gains | 6
Gross Unrealized Losses | (1)
Aggregate Fair Value | 10,247
Certificates of Deposit [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Amortized Cost | 1,768
Gross Unrealized Gains |
Gross Unrealized Losses | (2)
Aggregate Fair Value | $ 1,766

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- Definition This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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- Definition Amount of debt securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 2 -Subparagraph (b)-(g) -URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62557-112803 + Details
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- Definition Amount of accumulated pre-tax unrealized gains before deducting pre-tax unrealized losses on investments in available-for-sale securities impacting investments. + References No definition available. + Details
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- Definition Amount of accumulated pre-tax unrealized loss before deducting pre-tax unrealized gain on investments in available-for-sale debt securities impacting investments. + References No definition available. + Details
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