Fair Values of Financial Instruments - Summary of Reconciliation of Acquisition Related Contingent Consideration (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Payment of acquisition related contingent consideration		$ 24,683	$ 16,738	$ 13,550
Unfavorable fair value adjustment		28,767	3,226	(1,910)
Level 3 [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Opening balance - Level 3 liability		381,291	253,437
Measurement period adjustments	[1]	813	14,826
Payment of acquisition related contingent consideration		(24,683)	(16,738)
Reclassification to current payables		(3,290)	(2,340)
Unfavorable fair value adjustment		28,767	3,226
Ending balance - Level 3 liability		$ 382,898	381,291	$ 253,437
Level 3 [Member] | System Transformation Transactions [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Increase due to acquisitions	[2]		$ 128,880

[1] Measurement period adjustments relate to post-closing adjustments made in accordance with the terms and conditions of the applicable asset purchase agreement or asset exchange agreement for each System Transformation Transaction.

[2] Increase due to System Transformation Transactions acquisitions includes an increase in the acquisition related contingent consideration of $62.5 million in 2017 from the opening balance sheets for the distribution territories and regional manufacturing facilities acquired in the System Transformation during 2017, as disclosed in the financial statements in the Company’s filed periodic reports. These adjustments are for post-closing adjustments made in accordance with the terms and conditions of the applicable asset purchase agreement or asset exchange agreement for each System Transformation Transaction.