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Fair Value Measurements - Quantitative Information about Level 3 Fair Value Measurements (Details) | Mar. 31, 2020 USD ($)
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Fair Value Measurement Inputs and Valuation Techniques [Line Items] |
Valuation Adjustment For Level Three Asset and Liability | $ 5,100,000
Auction rate securities |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |
Valuation Adjustment For Level Three Asset and Liability | 4,200,000
Auction Rate Securities Purchase Commitment |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |
Valuation Adjustment For Level Three Asset and Liability | $ 887,000

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