Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities
Net income (loss)	$ 8,125	$ (20,029)
Adjustments to reconcile net income (loss) to net cash used in operating activities
Depreciation and amortization	6,024	6,870
Provision for severance benefits	5,771	7,260
Amortization of debt issuance costs and original issue discount	173	162
Loss (gain) on foreign currency, net	(8,857)	4,179
Restructuring gain	(7,785)
Stock-based compensation	536	185
Other	(10)	(242)
Changes in operating assets and liabilities
Accounts receivable, net	7,716	133
Inventories, net	(11,946)	(1,701)
Other receivables	(326)	6,140
Other current assets	(1,559)	(1,329)
Accounts payable	4,920	5,902
Other accounts payable	(3,748)	(4,881)
Accrued expenses	(3,729)	(7,626)
Deferred revenue	(9,777)	(1,604)
Other current liabilities	828	(170)
Other non-current liabilities	(325)	(220)
Payment of severance benefits	(4,098)	(1,341)
Other	(114)	(367)
Net cash used in operating activities	(18,181)	(8,679)
Cash flows from investing activities
Purchase of plant, property and equipment	(4,288)	(557)
Payment for intellectual property registration	(237)	(77)
Collection of guarantee deposits	374
Proceeds from settlement of hedge collateral	3,993
Payment of guarantee deposits	(14)	(411)
Other	10	15
Net cash used in investing activities	(162)	(1,030)
Cash flows from financing activities
Net cash provided by financing activities	0	0
Effect of exchange rates on cash and cash equivalents	988	(1,330)
Net decrease in cash and cash equivalents	(17,355)	(11,039)
Cash and cash equivalents
Beginning of the period	90,882	102,434
End of the period	73,527	91,395
Supplemental cash flow information
Cash paid for interest	7,453	7,683
Cash paid (refunded) for income taxes	(315)	303
Non-cash operating activities
Insurance proceeds in restricted cash reclassified from other receivables (Note 17)	(29,571)
Non-cash investing activities
Property, plant and equipment additions in other accounts payable	$ 605	$ 785