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Fair Value Measurements - Schedule of fair value on a recurring basis (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018
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Fair Value, Inputs, Level 1 [Member] |  |
Assets: |  |
Money market funds | $ 398 | $ 481
Fair Value, Inputs, Level 2 [Member] |  |
Assets: |  |
Short-term investments | 82,835 |
Company-owned life insurance | 12,185 | 10,464
Fair Value, Inputs, Level 3 [Member] |  |
Liabilities: |  |
Contingent consideration | $ 8,299 | $ 20,039

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- Definition Fair value Of contingent consideration liability. + References No definition available. + Details
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- Definition Fair value of company owned life insurance. + References No definition available. + Details
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- Definition Fair value of money market funds. + 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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