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Goodwill and Intangible Assets Goodwill (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Mar. 27, 2016 | Mar. 27, 2016 | Sep. 27, 2015
Goodwill |  |  |
Balance at beginning of the period |  | $ 601,379 |
Goodwill additions |  | 104,454 |
Goodwill adjustments |  | 2,000 |
Foreign exchange impact |  | 8,411 |
Balance at end of the period | $ 716,244 | 716,244 |
CEG |  |  |
Goodwill |  |  |
Goodwill adjustments | 2,000 |  |
Coffey and INDUS |  |  |
Goodwill |  |  |
Balance at end of the period | 104,454 | 104,454 |
WEI |  |  |
Goodwill |  |  |
Balance at beginning of the period |  | 210,748 |
Goodwill additions |  | 9,030 |
Foreign exchange impact |  | 713 |
Balance at end of the period | 220,491 | 220,491 |
Gross amounts of goodwill | 302,900 | 302,900 | $ 293,100
Accumulated impairment | 82,400 | 82,400 | 82,400
WEI | Coffey and INDUS |  |  |
Goodwill |  |  |
Goodwill additions | 9,000 |  |
RME |  |  |
Goodwill |  |  |
Balance at beginning of the period |  | 390,631 |
Goodwill additions |  | 95,424 |
Goodwill adjustments |  | 2,000 |
Foreign exchange impact |  | 7,698 |
Balance at end of the period | 495,753 | 495,753 |
Gross amounts of goodwill | 529,000 | 529,000 | 423,800
Accumulated impairment | 33,200 | $ 33,200 | $ 33,200
RME | Coffey and INDUS |  |  |
Goodwill |  |  |
Goodwill additions | $ 95,400 |  |

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