Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Operating activities:
Net income (loss)	$ 25,537,000	$ (1,898,000)	$ 36,877,000
Adjustments to reconcile net income to net cash provided by operating activities, net of effects of acquisitions :
Depreciation and amortization	21,441,000	23,480,000	18,518,000
Deferred income taxes	1,871,000	(1,052,000)	(3,852,000)
(Gain) loss on sale of property, plant and equipment	(39,000)	(252,000)	109,000
Provision for uncollectible accounts	6,034,000	357,000	(159,000)
Stock-based compensation expense	6,317,000	6,302,000	5,688,000
Excess tax benefit of exercised stock options and vesting of deferred shares	(3,261,000)	(1,802,000)	(1,730,000)
Other	240,000	238,000	208,000
Changes in operating assets and liabilities increasing (decreasing) cash, net of effects from acquisitions:
Accounts receivable	4,152,000	6,831,000	(31,395,000)
Costs and estimated earnings in excess of billings on uncompleted contracts	(17,930,000)	(13,063,000)	13,540,000
Inventories	606,000	272,000	(11,000)
Other assets and liabilities	7,380,000	11,558,000	351,000
Accounts payable	14,698,000	12,957,000	29,234,000
Billings on uncompleted contracts in excess of costs and estimated earnings	(38,377,000)	(11,736,000)	3,142,000
Accrued expenses	1,657,000	(7,754,000)	6,468,000
Net cash provided by operating activities	30,326,000	24,438,000	76,988,000
Investing activities:
Acquisition of property, plant and equipment	(13,939,000)	(15,773,000)	(23,589,000)
Acquisitions, net of cash acquired (Note 2)	(13,049,000)	(5,551,000)	(51,607,000)
Proceeds from asset sales	422,000	750,000	553,000
Net cash used by investing activities	(26,566,000)	(20,574,000)	(74,643,000)
Financing activities:
Advances under senior revolving credit facility	10,213,000	11,165,000	87,826,000
Repayments of advances under senior revolving credit facility	(19,017,000)	(13,982,000)	(76,205,000)
Repayment of acquired long-term debt	(1,858,000)	0	0
Payment of debt amendment fees	0	0	(657,000)
Open market purchase of treasury shares	(10,461,000)	(5,000,000)	0
Issuances of common stock	638,000	493,000	1,175,000
Excess tax benefit of exercised stock options and vesting of deferred shares	3,261,000	1,802,000	1,730,000
Proceeds from issuance of common stock under employee stock purchase plan	335,000	298,000	136,000
Repurchase of common stock for payment of statutory taxes due on equity-based compensation	(4,588,000)	(2,528,000)	(1,776,000)
Capital contributions from noncontrolling interest	10,892,000	8,546,000	0
Net cash provided (used) by financing activities	(10,585,000)	794,000	12,229,000
Effect of exchange rate changes on cash	(758,000)	(2,534,000)	(1,209,000)
Net increase (decrease) in cash and cash equivalents	(7,583,000)	2,124,000	13,365,000
Cash and cash equivalents, beginning of period	79,239,000	77,115,000
Cash and cash equivalents, end of period	71,656,000	79,239,000	77,115,000
Other cash flow information:
Cash paid during the period for income taxes	9,365,000	6,960,000	19,160,000
Cash paid during the period for interest	881,000	1,281,000	1,224,000
Non-cash investing:
Purchases of property, plant and equipment on account	193,000	439,000	527,000
Assumption of debt from acquisition	$ 1,858,000	$ 0	$ 0