CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flows from operating activities:
Net income (loss)	$ 29,744	$ (19,847)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	19,775	19,446
Deferred income taxes	134	807
Share-based compensation expense	25,004	23,585
Gain on investments	(2,388)	(1,200)
Impairment loss on equity investment of private company	3,189
Changes in assets and liabilities:
Accounts receivable, net	3,918	520
Inventories	(22,513)	(1,150)
Prepaid expenses and other assets	419	(4,710)
Accounts payable	8,755	594
Accrued liabilities and other payables	21,063	(91)
Net cash provided by operating activities	87,100	17,954
Cash flows from investing activities:
Purchase of severance-related insurance policies	(381)	(409)
Purchase of short-term investments	(188,161)	(159,388)
Proceeds from sales of short-term investments	98,742	90,321
Proceeds from maturities of short-term investments	30,717	37,760
Restricted cash deposit		(103)
Purchase of property and equipment	(20,413)	(10,265)
Purchase of equity investment in a private company		(1,438)
Net cash used in investing activities	(79,496)	(43,522)
Cash flows from financing activities:
Principal payments on capital lease obligations	(556)	(683)
Proceeds from exercise of share awards	9,829	7,109
Net cash provided by financing activities	9,273	6,426
Increase (decrease) in cash and cash equivalents	16,877	(19,142)
Cash and cash equivalents at beginning of period	51,326	63,164
Cash and cash equivalents at end of period	$ 68,203	44,022
As revised
Cash flows from operating activities:
Net income (loss)		(19,847)
Changes in assets and liabilities:
Net cash provided by operating activities		17,954
Cash flows from financing activities:
Net cash provided by financing activities		$ 6,426