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Goodwill and Intangible Assets (Details) (USD $)	0 Months Ended		6 Months Ended
Goodwill and Intangible Assets (Details) (USD $)	Sep. 29, 2014	Jun. 30, 2014	Mar. 29, 2015	Sep. 28, 2014
Goodwill information
Goodwill			$ 671,397,000us-gaap_Goodwill
Goodwill
Balance at beginning of the period	714,190,000us-gaap_Goodwill		714,190,000us-gaap_Goodwill
Foreign exchange translation			(42,793,000)us-gaap_GoodwillTranslationAdjustments
Balance at end of the period			671,397,000us-gaap_Goodwill
Impairment of goodwill	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss
WEI
Goodwill information
Goodwill			222,558,000
Goodwill
Balance at beginning of the period	238,086,000		238,086,000
Foreign exchange translation			(15,528,000)
Balance at end of the period			222,558,000
Gross amounts of goodwill			253,700,000	269,200,000
Accumulated impairment			31,100,000	31,100,000
RME
Goodwill information
Goodwill			448,839,000
Goodwill
Balance at beginning of the period	476,104,000		476,104,000
Foreign exchange translation			(27,265,000)
Balance at end of the period			448,839,000
Gross amounts of goodwill			475,200,000	502,500,000
Accumulated impairment			$ 26,400,000	$ 26,400,000