Discontinued Operations - Recorded Gain With the Sale of Cable Access HFC Business (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended	3 Months Ended	9 Months Ended
Sep. 26, 2014	Sep. 27, 2013	Sep. 27, 2013 HFC business [Member]	Sep. 27, 2013 HFC business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross Proceeds				$ 46,000
Inventories, net			10,579	10,579
Prepaid expenses and other current assets			612	612
Property and equipment, net			1,180	1,180
Goodwill de-recognized			14,547	14,547
Deferred revenue			(4,499)	(4,499)
Accrued liabilities			(939)	(939)
Total net assets sold and de-recognized			21,480	21,480
Less : Selling cost				2,473
Less : Tax effect				7,234
Gain on disposal, net of taxes	$ 0	$ 14,813	$ (6)	$ 14,813

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Disposal Group Including Discontinued Operation Direct Selling Costs

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Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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Amount of tax expense or benefit on gain (loss), not previously recognized, resulting from the sale of a business component.

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For the disposal group, including a component of the entity (discontinued operation), carrying value of obligations incurred and payable pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include interest, rent, salaries, and utilities.

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Amount of deferred revenue attributable to disposal group.

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For the disposal group, including a component of the entity (discontinued operation), carrying amount of goodwill (adjusted for any amortization recognized prior to adoption of FAS 142 and impairment charges).

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For the disposal group, including a component of the entity (discontinued operation), carrying amount of inventories (net of all valuation allowances and write-downs).

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For the disposal group, including a component of the entity (discontinued operation), carrying amount of assets not otherwise specified in the taxonomy that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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For the disposal group, including a component of the entity (discontinued operation), carrying value (net of accumulated depreciation and any write-downs) of tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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