Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Balance Sheet Components - Property and equipment, net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Mar. 31, 2024
The Company and Summary of Significant Accounting Policies
Total property and equipment	$ 17,091	$ 17,238
Less: accumulated depreciation and amortization	(16,319)	(16,127)
Property and equipment, net	772	1,111	$ 644
Depreciation expense	640,000	518,000
Production equipment
The Company and Summary of Significant Accounting Policies
Total property and equipment	14,887	14,800
IT equipment
The Company and Summary of Significant Accounting Policies
Total property and equipment	1,127	1,212
Furniture and fixtures
The Company and Summary of Significant Accounting Policies
Total property and equipment	784	799
Leasehold improvements
The Company and Summary of Significant Accounting Policies
Total property and equipment	$ 293	388
Fixed assets in process
The Company and Summary of Significant Accounting Policies
Total property and equipment		$ 39