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Short Term Investments - Additional Information (Detail) (US Treasury Securities, USD $)
In Millions, unless otherwise specified |
9 Months Ended |
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Sep. 30, 2013
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| Investment [Line Items] | |
| Held to maturity securities, amortized cost | $ 180.1 |
| Held to maturity securities, carrying value | 180.1 |
| Held to maturity securities, fair value | $ 180.2 |
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Minimum
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| Investment [Line Items] | |
| Held to maturity securities maturity range | 3 months |
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Maximum
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| Investment [Line Items] | |
| Held to maturity securities maturity range | 1 year |
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- Details
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- Definition
Held To Maturity Securities Maturity No definition available.
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- Definition
Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity. No definition available.
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- Definition
Fair value of investments in debt securities classified as held-to-maturity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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