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Fair Value of Financial Instruments - Auction rate securities and Contingent consideration (Details) - Significant Unobservable Inputs (Level 3) - Weighted Average - Discounted cash flow | 9 Months Ended
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Sep. 30, 2017
Assets and liabilities measured at fair value on recurring basis |
Quantitative information for Level 3 Fair Value Measurements Assets |
Expected holding period | 3 months
Estimated discount rate (as a percent) | 12.00%
Auction rate securities |
Quantitative information for Level 3 Fair Value Measurements Assets |
Estimated yield (as a percent) | 1.27%
Expected holding period | 10 years
Estimated discount rate (as a percent) | 3.27%

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- Definition Represents the expected holding period, used as an input to measure fair value. + References No definition available. + Details
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- Definition Represents the liquidity discount, used as an input to measure fair value. + References No definition available. + Details
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