Reportable Segments - Summary of Segment Data (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2019	Jun. 29, 2018	Jun. 28, 2019	Jun. 29, 2018	Dec. 28, 2018
Revenues:
Revenues	$ 265,367	$ 290,213	$ 525,508	$ 605,055
Gross profit:
Total segment gross profit	48,169	46,065	92,966	94,869
Operating profit:
Total segment operating profit	8,971	22,664	17,151	49,572
ASSETS
Total segment assets	1,008,958	965,477	1,008,958	965,477	$ 965,477
SPS [Member]
Revenues:
Revenues	210,390	290,213	410,635	605,055
Gross profit:
Total segment gross profit	29,317	46,065	54,998	94,869
Operating profit:
Total segment operating profit	6,368	22,664	10,692	49,572
ASSETS
Total segment assets	819,970	802,715	819,970	802,715
SSB [Member]
Revenues:
Revenues	54,977		114,873
Gross profit:
Total segment gross profit	18,852		37,968
Operating profit:
Total segment operating profit	2,603		6,459
ASSETS
Total segment assets	$ 188,988	$ 162,762	$ 188,988	$ 162,762