Marketable Securities and Fair Value Measurements - Summary of Company's Available-for-Sale Securities (Detail) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
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| Schedule Of Available For Sale Securities [Line Items] | ||
| Fair Value | $ 10,234 | $ 0 |
| Cash Equivalents - Money Market Funds and Commercial Paper | ||
| Schedule Of Available For Sale Securities [Line Items] | ||
| Cost Basis | 85,434 | |
| Unrealized Gain | 0 | |
| Unrealized Loss | 0 | |
| Fair Value | 85,434 | |
| Marketable Securities, Current - Commercial Paper | ||
| Schedule Of Available For Sale Securities [Line Items] | ||
| Cost Basis | 10,234 | |
| Unrealized Gain | 0 | |
| Unrealized Loss | 0 | |
| Fair Value | $ 10,234 | |
| Maturity dates | 2019-01 | |
| Maturity dates | 2019-09 | |
| Cash Equivalents - Money Market Funds | ||
| Schedule Of Available For Sale Securities [Line Items] | ||
| Cost Basis | 51,751 | |
| Unrealized Gain | 0 | |
| Unrealized Loss | 0 | |
| Fair Value | $ 51,751 |
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- Definition Available for sale securities maturities date range end. No definition available.
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- Definition Available for sale securities maturities date range start. No definition available.
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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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