Acquisitions (Recognized Identifiable Assets Acquired and Liabilities Assumed) (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended
Oct. 31, 2014	Mar. 27, 2015	Sep. 26, 2014
Business Acquisition [Line Items]
Goodwill		$ 312,869us-gaap_Goodwill	$ 277,574us-gaap_Goodwill
Doremi Labs [Member]
Business Acquisition [Line Items]
Current assets	17,231
Inventories	16,372
Intangible assets	45,600
Goodwill	39,672
Current liabilities	(11,653)
Non-current liabilities	(8,820)
Cash payment to sellers	98,402
Contingent consideration liability	20,000	740
Purchase consideration	$ 99,142

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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The amount of inventory recognized as of the acquisition date.

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Amount of liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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