Agreement date.

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- Definition

Purchase Consideration, Percentage

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- Definition

Related Party Transaction Percentage Of Acquisition Fees

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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- Definition

Costs associated with revenues arising from an entity that is an affiliate of the reporting entity by means of direct or indirect ownership.

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Related-Party Transactions - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended		12 Months Ended
	Sep. 30, 2014	Jan. 31, 2014	Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Related Party Transaction [Line Items]
Transaction fees paid			$ 3.9
Revenue from unconsolidated affiliates				0.6us-gaap_RevenueFromRelatedParties	7.9us-gaap_RevenueFromRelatedParties
Costs incurred in connection with several transactions with unconsolidated affiliates				0.2us-gaap_AffiliateCosts	0.2us-gaap_AffiliateCosts
Accounts receivable from affiliates				0.4us-gaap_DueFromAffiliateCurrent
Related party transactions	5.75	13.00
Blackstone Management Partners L.L.C. [Member]
Related Party Transaction [Line Items]
Management fees incurred			4.4	2.6	2.1
Agreement date			Jul. 30, 2009
Percentage transaction fee on value of entity acquired			1.00%
Consideration paid / received on assets acquired / disposed			1.00%
Continental Cement Company, L.L.C. [Member]
Related Party Transaction [Line Items]
Sales to related parties			14.3	12.7	12.5
Accounts receivables due from related parties			$ 1.2	$ 0.2