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Fair Value Measurements - Financial Assets and Liabilities Carried at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Transfers between Levels |  |
Level 1 to Level 2 transfers, Assets | $ 0 |
Level 2 to Level 1 transfers, Assets | 0 |
Level 1 to Level 2 transfers, Liabilities | 0 |
Level 2 to Level 1 transfers, Liabilities | 0 |
Recurring |  |
Assets: |  |
Equity securities | 531 | $ 681
Liabilities: |  |
Contingent consideration | 75 | 75
Recurring | Significant Unobservable Inputs (Level 3) |  |
Assets: |  |
Equity securities | 531 | 681
Liabilities: |  |
Contingent consideration | $ 75 | $ 75

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