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Fair Value Measurements - Summary of Company's Fair Value Hierarchy for its Financial Assets and Liabilities (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Assets: |  |
Fair value of investments | $ 7,177 | $ 255
Liabilities |  |
Fair value of liabilities | (4,059) | (4,196)
Contingent Purchase Price [Member] |  |
Liabilities |  |
Fair value of liabilities | (4,059) | (4,196)
Money Market Funds [Member] |  |
Assets: |  |
Fair value of cash equivalents | 7,177 | 255
Level 1 [Member] |  |
Assets: |  |
Fair value of investments | 7,177 | 255
Level 1 [Member] | Money Market Funds [Member] |  |
Assets: |  |
Fair value of cash equivalents | 7,177 | 255
Level 3 [Member] |  |
Liabilities |  |
Fair value of liabilities | (4,059) | (4,196)
Level 3 [Member] | Contingent Purchase Price [Member] |  |
Liabilities |  |
Fair value of liabilities | $ (4,059) | $ (4,196)

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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + 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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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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