Summary of Securities (Detail) (USD $) In Millions, unless otherwise specified	Mar. 29, 2015	Dec. 28, 2014
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Fair Value	$ 2.2us-gaap_AvailableForSaleSecurities
Short-Term Available for Sale
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Amortized Cost	0.2	0.1
Gross Unrealized Losses	0	0
Fair Value	0.2	0.1
Short-Term Available for Sale \| U.S. Treasury Securities and Obligations of U.S. Government Agencies
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Amortized Cost	0.2	0.1
Gross Unrealized Losses	0	0
Fair Value	0.2	0.1
Long-Term Available for Sale
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Amortized Cost	1.8	2.0
Gross Unrealized Gains	0.2	0.2
Gross Unrealized Losses	0	0
Fair Value	2.0	2.2
Long-Term Available for Sale \| U.S. Treasury Securities and Obligations of U.S. Government Agencies
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Amortized Cost	1.7	1.8
Gross Unrealized Gains	0.2	0.2
Gross Unrealized Losses	0	0
Fair Value	1.9	2.0
Long-Term Available for Sale \| Corporate Debt Securities
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Amortized Cost	0.1	0.2
Gross Unrealized Losses	0	0
Fair Value	$ 0.1	$ 0.2

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 25

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Publisher FASB

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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