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Lease Agreements - Leased facilities (Details) $ in Millions | 6 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jun. 30, 2020 facility | Dec. 31, 2019 USD ($) | Dec. 17, 2019 facility | Dec. 18, 2019 facility
Leased facilities, Berkeley, California |  |  |  |
Leases |  |  |  |
Operating leases, number of leased facilities |  |  | 2 |
Number of operating leases terminated early |  |  |  | 2
Early termination fee | $ |  | $ 1.6 |  |
Lease termination loss | $ |  | $ 0.4 |  |
Leased facilities, Emeryville, California |  |  |  |
Leases |  |  |  |
Operating leases, number of leased facilities | 1 |  |  |

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- Definition Amount of gain (loss) on termination of lease before expiration of lease term. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 40 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77888415&loc=SL77918607-209975 + Details
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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 Amount of fee for early termination of operating lease. + References No definition available. + Details
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- Details
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- Details
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