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Fair Value Measurements - Summary of Company's Fair Value Hierarchy for its Financial Assets and Liabilities (Parenthetical) (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of liabilities | $ 4,269 | $ 4,196
Accrued Expenses and Other Current Liabilities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of liabilities | 1,800 | 1,800
Non-current Liabilities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of liabilities | $ 2,500 | $ 2,400

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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. + References No definition available. + Details
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- Definition Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities. + References No definition available. + Details
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