CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Jul. 29, 2017	Jul. 30, 2016
Operating activities
Net loss	$ (4,466)	$ (11,642)
Adjustments to reconcile net loss to cash provided by (used in) operating activities:
Depreciation and amortization	1,862	1,653
Loss from equity method investments		72
Impairment of long-lived assets	9
Provision for doubtful accounts	211	171
(Gains) losses on foreign currency transactions	(106)	226
Deferred income taxes	(596)
Stock-based compensation	1,397	992
Tax benefit from exercise of stock options		22
Gain on disposition of property and equipment		(7)
Amortization of held-to-maturity investments	474	661
Changes in operating assets and liabilities:
Accounts receivable	43,577	23,019
Unbilled receivables and retentions	3,367	4,406
Inventories	(11,941)	(6,619)
Income tax receivable	(2,969)	(4,250)
Prepaid expenses and other assets	377	(17)
Accounts payable	(6,238)	(6,336)
Other liabilities	(3,676)	(3,594)
Net cash provided by (used in) operating activities	21,282	(1,243)
Investing activities
Acquisition of property and equipment	(2,973)	(2,634)
Redemptions of held-to-maturity investments	59,280	28,820
Purchases of held-to-maturity investments	(41,806)	(27,487)
Proceeds from the sale of property and equipment		7
Sales and redemptions of available-for-sale investments	450	400
Net cash provided by (used in) investing activities	14,951	(894)
Financing activities
Principal payments of capital lease obligations	(92)	(95)
Tax withholding payment related to net settlement of equity awards	(212)
Exercise of stock options	1,640	258
Net cash provided by financing activities	1,336	163
Net increase (decrease) in cash and cash equivalents	37,569	(1,974)
Cash and cash equivalents at beginning of period	79,904	124,287
Cash and cash equivalents at end of period	117,473	122,313
Cash paid during the period for:
Income taxes	1,803	1,786
Non-cash activities
Unrealized gain on investments, net of deferred tax expense of $2 and $12, respectively	2	18
Reclassification from share-based liability compensation to equity	384	307
Acquisitions of property and equipment included in accounts payable	$ 644	$ 321