Marketable Securities - Maturities of Held to Maturity Investments (Details) $ in Thousands |
Sep. 30, 2017
USD ($)
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| Marketable Securities [Abstract] | |
| Held-to-maturity investments, maturities due within one year | $ 47,814 |
| Held-to-maturity investments, maturities due in one to five years | 69,991 |
| Held-to-maturity investments, total maturities due | $ 117,805 |
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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 Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the next fiscal year through the fifth fiscal year following the latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the next fiscal year following the latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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