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Organization and Summary of Significant Accounting Policies - Additional Information (Details) shares in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2020 USD ($) shares | Dec. 31, 2020 USD ($) segment subsidiary shares | Dec. 31, 2019 USD ($) shares | Dec. 31, 2018 USD ($)
Organization And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Number of wholly owned Irish subsidiaries | subsidiary |  | 2 |  |
Number of operating segments | segment |  | 1 |  |
Number of reportable segments | segment |  | 1 |  |
Accrued interest receivables write-off threshold period | 90 days | 90 days |  |
Accrued interest receivables | $ 3,700,000 | $ 3,700,000 |  |
Accrued interest receivables write-off |  | 0 | $ 0 | $ 0
Depreciation |  | 8,600,000 | 7,400,000 | 4,000,000.0
Advertising expense |  | $ 64,800,000 | $ 40,600,000 | $ 20,500,000
PRSUs |  |  |  |
Organization And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Ending Balance, Unvested (in shares) | shares | 0.2 | 0.2 | 0.3 |
2.25% Convertible senior notes due 2024 |  |  |  |
Organization And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Shares issued to settle notes at initial conversion rate (in shares) | shares | 5.0 |  |  |
ESPP |  |  |  |
Organization And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Share based compensation arrangement by share based payment award purchase period |  | 6 months |  |
Revenue, Product and Service Benchmark | Customer Concentration Risk | Largest two customers |  |  |  |
Organization And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Concentration risk, percentage |  | 86.00% | 86.00% |
Revenue, Product and Service Benchmark | Customer Concentration Risk | Largest three customers |  |  |  |
Organization And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Concentration risk, percentage |  |  |  | 93.00%
Minimum |  |  |  |
Organization And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Property, plant and equipment, useful life |  | 3 years |  |
Share-based compensation arrangement by share-based payment award, award requisite service period |  | 3 years |  |
Maximum |  |  |  |
Organization And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Property, plant and equipment, useful life |  | 7 years |  |
Share-based compensation arrangement by share-based payment award, award requisite service period |  | 4 years |  |

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