Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Operating activities:
Net income (loss)	$ (3,037)	$ 6,151
Adjustments to reconcile net income (loss) to net cash provided (used) by operating activities:
Depreciation and amortization	4,639	4,779
Stock-based compensation expense	2,218	3,024
Operating lease and fixed asset impairments due to restructuring	150	0
Deferred income tax	289	1,990
Gain on sale of property, plant and equipment	(941)	(93)
Provision for uncollectible accounts	(64)	224
Other	101	84
Changes in operating assets and liabilities increasing (decreasing) cash:
Accounts receivable	(10,769)	3,594
Costs and estimated earnings in excess of billings on uncompleted contracts	1,854	30,087
Inventories	(291)	456
Other assets and liabilities	(8,018)	(297)
Accounts payable	(4,431)	(15,240)
Billings on uncompleted contracts in excess of costs and estimated earnings	(366)	24,565
Accrued expenses	3,646	(3,220)
Net cash provided (used) by operating activities	(15,020)	56,104
Investing activities:
Capital expenditures	(2,777)	(8,684)
Proceeds from asset sales	1,074	151
Net cash used by investing activities	(1,703)	(8,533)
Financing activities:
Advances under senior secured revolving credit facility	0	8,984
Repayments of advances under senior secured revolving credit facility	0	(2,872)
Proceeds from issuance of common stock under employee stock purchase plan	82	83
Repurchase of common stock for payment of statutory taxes due on equity-based compensation	(1,536)	(3,394)
Net cash provided (used) by financing activities	(1,454)	2,801
Effect of exchange rate changes on cash and cash equivalents	316	(198)
Increase (decrease) in cash and cash equivalents	(17,861)	50,174
Cash and cash equivalents, beginning of period	100,036	89,715
Cash and cash equivalents, end of period	82,175	139,889
Supplemental disclosure of cash flow information:
Income taxes	122	5,069
Interest paid	470	417
Non-cash investing and financing activities:
Purchases of property, plant and equipment on account	$ 0	$ 263