Schedule of Available for Sale Securities by Contractual Maturity (Detail) (USD $) In Millions, unless otherwise specified	Mar. 29, 2015
Investments Classified by Contractual Maturity Date [Line Items]
Due in one year or less, Amortized Cost	$ 0.2
Due after one year through five years, Amortized Cost	0.7
Due after five years, Amortized Cost	1.1
Total available for sale securities, Amortized Cost	2.0
Due in one year or less, Fair Value	0.2
Due after one year through five years, Fair Value	0.8
Due after five years, Fair Value	1.2
Total available for sale securities, Fair Value	$ 2.2us-gaap_AvailableForSaleSecurities

Available for sale Securities, Debt Maturities, after Five Years, Amortized Cost

No definition available.

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- Definition

This item represents the fair value of debt securities which are expected to mature after five years from the balance sheet date which are categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

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- Definition

This item represents the cost of debt 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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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- Definition

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

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- Definition

Amount after adjustments of available-for-sale debt securities at cost, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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

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-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.2)

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- Definition

Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

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-Subparagraph (SX 210.5-02.2)

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- Definition

Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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