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Other Balance Sheet Accounts Details - Additional Information (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Property, Plant and Equipment [Abstract]      
Depreciation expense $ 4.2 $ 5.0 $ 6.4
Amortization expense related to intangible assets $ 1.4   $ 1.4
Weighted average useful life of purchased intangible assets (in years) 7 months 6 days