Business Segments (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 01, 2018 USD ($)	Apr. 02, 2017 USD ($)	Apr. 01, 2018 USD ($) segment	Apr. 02, 2017 USD ($) segment	Jul. 02, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of segments | segment			2	2
Net sales	$ 93,938	$ 95,410	$ 274,520	$ 293,176
Gross profit	17,676	16,915	52,693	50,098
Selling and administrative expenses	13,253	12,862	42,532	39,198
Internal research and development expenses	307	424	1,548	1,308
Depreciation and amortization	3,240	3,584	10,046	10,983
Operating income (loss)	2,314	1,530	2,995	3,083
Capital expenditures	680	2,259	3,779	4,829
Total assets	224,607	217,143	224,607	217,143	$ 217,143
Operating Segments | MDS
Segment Reporting Information [Line Items]
Net sales	59,786	61,084	173,447	193,468
Gross profit	7,164	6,690	20,116	22,341
Selling and administrative expenses	5,487	5,684	17,001	17,221
Internal research and development expenses	0	0	0	0
Depreciation and amortization	2,149	2,577	6,724	7,901
Operating income (loss)	204	(722)	(1,489)	(250)
Capital expenditures	384	1,291	2,699	1,960
Total assets	146,739	142,513	146,739	142,513
Operating Segments | ECP
Segment Reporting Information [Line Items]
Net sales	37,199	37,053	110,065	106,995
Gross profit	10,512	10,225	32,577	27,757
Selling and administrative expenses	3,454	4,160	10,604	11,529
Internal research and development expenses	307	424	1,548	1,308
Depreciation and amortization	517	563	1,613	1,755
Operating income (loss)	6,422	5,270	19,411	13,781
Capital expenditures	121	260	516	1,018
Total assets	76,610	64,694	76,610	64,694
Unallocated
Segment Reporting Information [Line Items]
Net sales	0	0	0	0
Gross profit	0	0	0	0
Selling and administrative expenses	4,312	3,018	14,927	10,448
Internal research and development expenses	0	0	0	0
Depreciation and amortization	574	444	1,709	1,327
Operating income (loss)	(4,312)	(3,018)	(14,927)	(10,448)
Capital expenditures	175	708	564	1,851
Total assets	1,258	9,936	1,258	9,936
Eliminations
Segment Reporting Information [Line Items]
Net sales	(3,047)	(2,727)	(8,992)	(7,287)
Gross profit	0	0	0	0
Selling and administrative expenses	0	0	0	0
Internal research and development expenses	0	0	0	0
Depreciation and amortization	0	0	0	0
Operating income (loss)	0	0	0	0
Capital expenditures	0	0	0	0
Total assets	$ 0	$ 0	$ 0	$ 0