Operating Segments and Geographic Information - Reconciliation of Total Reportable Segments' Revenues and EBITDA to Consolidated Revenues and Consolidated Income from Continuing Operations Before Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2016	Jun. 28, 2015	Jul. 03, 2016	Jun. 28, 2015
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Revenues	$ 601,631	$ 585,755	$ 1,143,128	$ 1,132,712
Amortization of intangibles	(26,263)	(25,917)	(51,795)	(52,421)
Severance, restructuring, and acquisition integration costs	(5,869)	(4,907)	(14,277)	(19,390)
Depreciation expense	(12,000)	(11,700)	(23,700)	(23,200)
Consolidated operating income	62,241	44,143	103,205	49,041
Interest expense, net	(24,049)	(24,769)	(48,445)	(48,615)
Consolidated income from continuing operations before taxes	38,192	19,374	54,760	426
Reportable Segment [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Revenues	603,381	598,513	1,147,181	1,167,964
Deferred revenue adjustments	(1,750)	(12,758)	(4,053)	(35,252)
Total Segment EBITDA	108,335	100,300	198,401	188,597
Amortization of intangibles	(26,263)	(25,917)	(51,795)	(52,421)
Deferred gross profit adjustments	(1,750)	(13,440)	(4,053)	(35,098)
Severance, restructuring, and acquisition integration costs	(5,869)	(4,907)	(14,277)	(19,390)
Depreciation expense	(11,987)	(11,692)	(23,650)	(23,233)
Purchase accounting effects related to acquisitions			(195)	(9,422)
Income from equity method investment	661	343	491	1,111
Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated operating income	$ (886)	$ (544)	$ (1,717)	$ (1,103)