Investments and Fair Value Measurements - Category of Financial Instruments Not Held at Fair Value (Parenthetical) (Detail) - Level 1 - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 31, 2017 |
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| Carrying Amount | ||
| Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] | ||
| Cash equivalents | $ 17,000 | $ 16,500 |
| Fair Value | ||
| Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] | ||
| Cash equivalents | $ 17,000 | $ 16,500 |
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- Definition Cash equivalents, fair value disclosure. No definition available.
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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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