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Leases - Additional Information (Detail) - USD ($) |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 27, 2024 | Dec. 31, 2024 | Sep. 30, 2024 | Dec. 31, 2023
Lessee Lease Description [Line Items] |  |  |  |
Lessee, Operating Lease, Option to Terminate |  | As part of its continuing efforts to reduce operating expenses and preserve cash, on September 27, 2024, the Company entered into an Agreement for Termination of Lease and Voluntary Surrender of Premises (“Lease Termination Agreement”) with its landlord, ARE-San Francisco No.43 Owner, LLC (“ARE”) related to the Company’s operating lease of its corporate headquarters in San Francisco, California. The Lease Termination Agreement modifies the lease agreement dated as of September 22, 2006, as subsequently amended and accelerates the expiration date of the term of the Lease from 2028 to no later than December 31, 2024. |  |
Lessee, Operating Lease, Existence of Option to Terminate [true false] |  | true |  |
Lease termination settlement amount | $ 10,000,000 |  |  |
Lease termination settlement one time cash payment | 8,300,000 |  |  |
Lease termination, remaining security deposit | $ 1,700,000 |  |  |
Operating lease right-of-use assets |  | $ 0 |  | $ 64,939,000
Gain on lease termination |  | $ 1,700,000 |  |
Derecognized [Member] |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |
Operating lease right-of-use assets |  |  | $ 56,100,000 |
Operating lease liability |  |  | $ 68,500,000 |
Office Equipment [Member] | Maximum [Member] |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |
Lessee, operating lease, lease term |  | 6 years |  |

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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 -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 40 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479092/842-20-40-1 + 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-3 + Details
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- Definition Indicates (true false) whether lessee has option to terminate operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-3 + Details
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- Definition Description of terms and conditions of option to terminate lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-3 + Details
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- Definition Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-3 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479041/842-20-45-1 + Details
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