Operating Segments - 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. 02, 2017	Jul. 03, 2016	Jul. 02, 2017	Jul. 03, 2016
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated Revenues	$ 610,633	$ 601,631	$ 1,162,014	$ 1,143,128
Amortization of intangibles	(27,113)	(26,263)	(50,782)	(51,795)
Depreciation expense	(11,500)	(12,000)	(22,900)	(23,700)
Severance, restructuring, and acquisition integration costs	(9,560)	(5,869)	(16,160)	(14,277)
Operating income	62,481	62,241	113,818	103,205
Interest expense, net	(23,533)	(24,049)	(47,039)	(48,445)
Loss on debt extinguishment	(847)	0	(847)	0
Income before taxes	38,101	38,192	65,932	54,760
Reportable Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Segment Revenues	610,633	603,381	1,162,014	1,147,181
Deferred revenue adjustments	0	(1,750)	0	(4,053)
Consolidated Revenues	610,633	601,631	1,162,014	1,143,128
Total Segment EBITDA	110,227	108,335	203,337	198,401
Amortization of intangibles	(27,113)	(26,263)	(50,782)	(51,795)
Depreciation expense	(11,528)	(11,987)	(22,911)	(23,650)
Severance, restructuring, and acquisition integration costs	(9,560)	(5,869)	(16,160)	(14,277)
Purchase accounting effects related to acquisitions	(1,167)	0	(1,167)	(195)
Deferred gross profit adjustments	0	(1,750)	0	(4,053)
Income from equity method investment	2,277	661	3,284	491
Eliminations
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating income	$ (655)	$ (886)	$ (1,783)	$ (1,717)