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Revenue Recognition - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended |  |
--- | --- | --- | ---
Dec. 30, 2018 | Dec. 31, 2017 | Oct. 01, 2018 | Sep. 30, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Decrease to retained earnings upon adoption of new accounting guidance | $ (977,543) |  |  | $ (944,965)
Increase to contract assets due to adoption of new accounting guidance | (126,545) |  |  | (142,882)
Contracts liabilities | (155,585) |  |  | (143,270)
Increase to deferred tax assets due to adoption of new accounting guidance | 8,448 |  |  | 8,607
Contract liability revenue recognized during the period | 56,200 |  |  |
Liabilities for anticipated losses | 13,300 |  |  | 13,600
Estimated cost to complete the related contracts |  |  |  | $ 18,400
Impact of the Adoption of ASC 606 | Accounting Standards Update 2014-09 |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Decrease to retained earnings upon adoption of new accounting guidance |  |  | $ 2,800 |
Increase to contract assets due to adoption of new accounting guidance |  |  | 5,000 |
Contracts liabilities |  |  | 1,100 |
Increase to deferred tax assets due to adoption of new accounting guidance |  |  | $ 1,100 |
CIG |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Net unfavorable operating income adjustments | $ 400 | $ 700 |  |

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