Balance sheet components (Tables)

12 Months Ended

Dec. 31, 2019

Balance Sheet Related Disclosures [Abstract]

Restricted Cash

Restricted cash was as follows (in thousands):

	December 31,
	2019		2018
Restricted in connection with notes payable and short-term borrowing (see Note 11)	$	2,559	$	2,589
Restricted in connection with asset purchase agreement (see Note 9)	1,999		2,019
Restricted in connection with a current legal dispute with APAT OE (See Note 9)	5,989		5,156
Restricted in connection with government grants received in advance	425		1,289
Total restricted cash	$	10,972	$	11,053
Reported as:
Restricted cash	$	10,972	$	11,053

The Company’s consolidated subsidiaries operating in China and Japan are restricted from transferring funds or assets to its parent company in the form of cash dividends, loans or advances. As of December 31, 2019 and December 31, 2018, the Company's consolidated subsidiaries had $21.1 million and $20.9 million, respectively, of restricted net assets. This compares to the Company's consolidated net assets of $160.2 million and $160.2 million as of December 31, 2019 and December 31, 2018, respectively, which consisted of (in thousands):

	December 31, 2019		December 31, 2018
Cash restricted in China as a result of ongoing litigation and unfulfilled government grants	$	10,936	$	11,018
China earnings restricted to fund statutory common reserves in China	9,240		9,005
Loan agreements in Japan requiring local subsidiaries to maintain minimum net asset levels	920		909
Total restricted net assets in the Company's consolidated subsidiaries	$	21,096	$	20,932

Accounts Receivable, Net

Accounts receivable, net were as follows (in thousands): 

	December 31,
	2019			2018
Accounts receivable	$	68,988		$	74,343
Trade notes receivable	156			672
Allowance for doubtful accounts	(254		)	(264		)
	$	68,890		$	74,751

Summary of Movement in Allowance for Doubtful Accounts

The table below summarizes the movement in the Company’s allowance for doubtful accounts (in thousands): 

Balance at December 31, 2016	$	(425	)
Provision for bad debt, net	(577		)
Write-offs, net of recoveries	376
Balance at December 31, 2017	(626		)
Reversal of provision for bad debt, net	428
Write-offs, net of recoveries	(66		)
Balance at December 31, 2018	(264		)
Reversal of provision for bad debt, net	15
Write-offs, net of recoveries	(5		)
Balance at December 31, 2019	$	(254	)

Inventories, net

Inventories were as follows (in thousands): 

	December 31,
	2019		2018
Raw materials	$	19,350	$	27,806
Work in process	12,262		13,044
Finished goods(1)	15,318		11,309
	$	46,930	$	52,159

 

(1) Included in finished goods was $1.6 million and $5.6 million of inventory at customer vendor managed inventory locations at December 31, 2019 and 2018, respectively. 

Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets were as follows (in thousands):

	December 31,
	2019		2018
Prepaid taxes and taxes receivable	6,979		$	5,461
Transition services agreement receivable (see Note 9)	11,861		11,999
Deposits and other prepaid expenses	2,512		3,020
Other receivable	4,499		6,125
	$	25,851	$	26,605

Property, Plant and Equipment, Net

Property, plant and equipment, net were as follows (in thousands): 

	December 31,
	2019			2018
Land	$	3,197		$	3,157
Buildings	23,624			23,379
Machinery and equipment	181,596			187,746
Furniture, fixtures, software and office equipment	10,736			10,201
Leasehold improvements	22,058			22,000
	241,211			246,483
Less: Accumulated depreciation	(160,078		)	(146,393		)
	$	81,133		$	100,090

Accrued and Other Current Liabilities

Accrued and other current liabilities were as follows (in thousands): 

	December 31,
	2019		2018
Employee-related	$	17,877	$	14,899
Transition services agreement payables (see Note 9)	11,765		11,769
Asset sale related contingent liabilities (see Note 9)	6,664		6,751
Operating lease liabilities, current	2,086		—
Income and other taxes payable	2,036		1,580
Deferred revenue, current	—		1,114
Accrued warranty	712		672
Rusnano payment derivative	—		2,000
Accrued litigation settlement	—		2,645
Other accrued expenses	6,341		8,858
	$	47,481	$	50,288

Accrued Warranty

The table below summarizes the movement in the warranty accrual, which is included in accrued and other current liabilities (in thousands): 

	Years ended December 31,
	2019			2018			2017
Beginning balance	$	672		$	1,334		$	678
Warranty accruals	782			399			1,263
Settlements	(742		)	(1,061		)	(607		)
Ending balance	$	712		$	672		$	1,334

Other Noncurrent Liabilities

Other noncurrent liabilities were as follows (in thousands): 

	December 31,
	2019		2018
Pension and other employee-related	$	4,125	$	4,529
Deferred rent	—		3,058
Government grant	1,380		2,108
Deferred income tax liabilities	528		—
Capital lease obligation	—		282
*Asset retirement obligations	3,529		3,391
Other	52		131
	$	9,614	$	13,499

 

*Asset retirement obligations are legal obligations associated with the retirement of long-lived assets pertaining to leasehold improvements. In 2019 accretion related to the asset retirement obligations was $0.2 million.