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BALANCE SHEET COMPONENTS (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | --- | ---
Cash and cash equivalents: |  |  |
Cash and cash equivalents | $ 132,653 | $ 135,311 |
Restricted cash | 2,998 | 3,167 |
Cash, cash equivalents and restricted cash | 135,651 | 138,478 | $ 128,884
Inventories: |  |  |
Finished goods | 11,171 | 7,779 |
Raw materials | 1,145 | 799 |
Reserve for obsolescence | (151) | (180) |
Inventories, net | 12,165 | 8,398 |
Property and equipment: |  |  |
Office equipment | 537 | 530 |
Office software | 918 | 916 |
Machinery | 29 | 30 |
Furniture and fixtures | 319 | 276 |
Leasehold improvements | 1,022 | 957 |
Construction in progress (including internal-use software development costs) | 19 | 10 |
Property and equipment, at cost | 2,844 | 2,719 |
Accumulated depreciation and amortization | (1,910) | (1,570) |
Property and equipment, net | 934 | 1,149 |
Other accrued expenses: |  |  |
Sales returns | 801 | 614 |
Employee-related expense | 4,051 | 5,568 |
Warehousing, inventory-related and other | 1,269 | 1,423 |
Other accrued expenses | 6,121 | 7,605 |
Deferred revenue: |  |  |
Deferred revenue | 6,795 | 4,455 |
China |  |  |
Cash and cash equivalents: |  |  |
Cash and cash equivalents | 11,100 |  |
Unshipped product |  |  |
Deferred revenue: |  |  |
Deferred revenue | 4,574 | 2,411 |
Auto ship advances |  |  |
Deferred revenue: |  |  |
Deferred revenue | 1,876 | 1,665 |
Other |  |  |
Deferred revenue: |  |  |
Deferred revenue | 345 | 379 |
Cash |  |  |
Cash and cash equivalents: |  |  |
Cash and cash equivalents | 47,323 | 61,703 |
Cash equivalents |  |  |
Cash and cash equivalents: |  |  |
Cash and cash equivalents | $ 85,330 | $ 73,608 |

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