Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities
Net income	$ 7,322	$ 37,422
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	5,583	4,208
Deferred income taxes	818	6,767
Stock-based compensation expense	6,140	5,603
Provision for excess and obsolete inventory	1,961	1,657
Changes in operating assets & liabilities:
Accounts receivable	29,232	(10,222)
Inventories	(16,602)	(4,867)
Prepaid expenses and other current assets	(155)	49
Accounts payable and other current liabilities	(22,887)	(10,872)
Deferred revenue	4,864	1,245
Income taxes	(185)	(61)
Other assets and liabilities	(16,436)	(13,709)
Net cash (used in) provided by operating activities	(345)	17,220
Cash flows from investing activities
Expenditures for property, plant and equipment and capitalized software	(11,064)	(3,852)
Net cash used in investing activities	(11,064)	(3,852)
Cash flows from financing activities
Net settlement on restricted stock grants	(1,602)	(1,393)
Repurchase of common stock	(14,035)
Proceeds from Employee Stock Purchase Plan	407	437
Proceeds from exercise of stock options	3,039	1,289
Net cash (used in) provided by financing activities	(12,191)	333
Effect of exchange rate changes on cash and cash equivalents	871	1,012
Net (decrease) increase in cash, cash equivalents and restricted cash	(22,729)	14,713
Cash, cash equivalents and restricted cash at beginning of period	184,902	140,880
Cash, cash equivalents and restricted cash at end of period	$ 162,173	$ 155,593