Balance Sheet Components

3 Months Ended

Mar. 31, 2019

Balance Sheet Related Disclosures [Abstract]

Balance Sheet Components

5. Balance Sheet Components

Inventories

Inventories consisted of the following (in thousands):

	March 31, 2019		December 31, 2018
Raw materials	$	5,534	$	279
Work in process		18,349		14,395
Finished goods		2,594		2,844
Total inventories	$	26,477	$	17,518
Balance Sheet Classification
Inventories	$	2,672	$	7,873
Prepaid and other long-term assets		23,805		9,645
Total inventories	$	26,477	$	17,518

As of March 31, 2019, and December 31, 2018, long-term inventories of $23.8 million and $9.6 million, respectively are classified as prepaid and other long-term assets as these inventories are not expected to be sold within the next twelve months, and the amount is deemed recoverable.

As of March 31, 2019, and December 31, 2018, we have made prepayments to manufacturers for the purchase of inventories. These are classified as short and long-term assets based on when the inventories are expected to be utilized in the manufacturing process and/or sold within the next twelve months.

As of March 31, 2019, we maintain a reserve of $6.6 million for excess and obsolescence inventories. We recorded a related charge to cost of sales of $3.9 million during the three months ended March 31, 2019. In developing the estimate for inventory reserve, we used estimates of demand. If it is determined that inventory utilization will further diminish based on estimates of demand, additional inventory write-downs may be required.

Prepaid and Other Long-Term Assets

Prepaid and other long-term assets consist of the following (in thousands):

	March 31, 2019		December 31, 2018
Long-term inventories	$	23,805	$	9,645
Prepaid manufacturing and others		9,550		10,932
Total prepaid and other long-term assets	$	33,355	$	20,577

As of March 31, 2019 and December 31, 2018, long-term prepaid manufacturing of $7.8 million and $10.9 million, respectively, are classified as prepaid and other long-term assets as these inventories are not expected to be utilized in the manufacturing process and/or sold within the next twelve months.

Accrued and Other Liabilities

Accrued and other liabilities consist of the following (in thousands):

	March 31, 2019		December 31, 2018
Manufacturing related	$	8,571	$	5,465
Compensation and employee benefits		7,412		10,794
Current portion of lease liability		2,683		—
Others		9,747		6,051
Total accrued and other liabilities	$	28,413	$	22,310