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Pension and Other Postretirement Benefit Plans - Schedule of Fair Value of Pension Plan Assets (Details) - USD ($) $ in Thousands | Sep. 27, 2019 | Sep. 28, 2018 | Sep. 29, 2017
--- | --- | --- | ---
U.S. Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | $ 390,210 | $ 390,829 | $ 147,788
U.S. Plans | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 235,596 | 259,065 |
U.S. Plans | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 154,614 | 131,736 |
U.S. Plans | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 | 6,176
U.S. Plans | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 28 |
U.S. Plans | Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 10,890 | 77,798 |
U.S. Plans | Domestic equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 10,890 | 13,861 |
U.S. Plans | Domestic equities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 63,937 |
U.S. Plans | Domestic equities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Domestic equities | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Overseas equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 26,699 |
U.S. Plans | Overseas equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 26,699 |
U.S. Plans | Overseas equities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Overseas equities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Overseas equities | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Domestic bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 200,084 | 143,123 |
U.S. Plans | Domestic bonds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 65,490 | 84,894 |
U.S. Plans | Domestic bonds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 134,594 | 58,229 |
U.S. Plans | Domestic bonds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Domestic bonds | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Overseas bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 20,020 | 10,508 |
U.S. Plans | Overseas bonds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 938 |
U.S. Plans | Overseas bonds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 20,020 | 9,570 |
U.S. Plans | Overseas bonds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Overseas bonds | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Cash and equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 28,972 | 6,631 |
U.S. Plans | Cash and equivalents | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 28,972 | 6,631 |
U.S. Plans | Cash and equivalents | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Cash and equivalents | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Cash and equivalents | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Mutual funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 130,244 | 126,042 |
U.S. Plans | Mutual funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 130,244 | 126,042 |
U.S. Plans | Mutual funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Mutual funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Mutual funds | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 28 |
U.S. Plans | Hedge funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Hedge funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Hedge funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
U.S. Plans | Hedge funds | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 28 |
Non-U.S. Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 1,916,637 | 1,867,481 | 1,076,928
Non-U.S. Plans | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 37,811 | 33,803 |
Non-U.S. Plans | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 1,412,705 | 1,333,707 |
Non-U.S. Plans | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 300,527 | 331,155 |
Non-U.S. Plans | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 165,594 | 168,816 |
Non-U.S. Plans | Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 36,668 | 68,510 |
Non-U.S. Plans | Domestic equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Domestic equities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 17,255 | 31,868 |
Non-U.S. Plans | Domestic equities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Domestic equities | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 19,413 | 36,642 |
Non-U.S. Plans | Overseas equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 232,727 | 371,984 |
Non-U.S. Plans | Overseas equities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Overseas equities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 182,600 | 327,309 |
Non-U.S. Plans | Overseas equities | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Overseas equities | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 50,127 | 44,675 |
Non-U.S. Plans | Domestic bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 340,633 | 223,614 |
Non-U.S. Plans | Domestic bonds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 252 |
Non-U.S. Plans | Domestic bonds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 306,225 | 222,282 |
Non-U.S. Plans | Domestic bonds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Domestic bonds | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 34,408 | 1,080 |
Non-U.S. Plans | Overseas bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 767,908 | 702,770 |
Non-U.S. Plans | Overseas bonds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Overseas bonds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 728,616 | 641,966 |
Non-U.S. Plans | Overseas bonds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Overseas bonds | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 39,292 | 60,804 |
Non-U.S. Plans | Cash and equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 37,795 | 41,304 |
Non-U.S. Plans | Cash and equivalents | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 37,811 | 33,482 |
Non-U.S. Plans | Cash and equivalents | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | (16) | 7,822 |
Non-U.S. Plans | Cash and equivalents | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Cash and equivalents | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year |  |  |
Non-U.S. Plans | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 137,472 | 144,142 |
Non-U.S. Plans | Real estate | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Real estate | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 24,735 | 26,987 |
Non-U.S. Plans | Real estate | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 97,539 | 99,587 | 58,974
Non-U.S. Plans | Real estate | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 15,198 | 17,568 |
Non-U.S. Plans | Insurance contracts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 77,266 | 99,970 |
Non-U.S. Plans | Insurance contracts | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Insurance contracts | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 4,478 | 4,188 |
Non-U.S. Plans | Insurance contracts | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 72,788 | 95,782 | 74,353
Non-U.S. Plans | Insurance contracts | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year |  |  |
Non-U.S. Plans | Derivatives |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | (26,587) |
Non-U.S. Plans | Derivatives | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 69 |
Non-U.S. Plans | Derivatives | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | (26,656) |
Non-U.S. Plans | Derivatives | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Derivatives | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year |  |  |
Non-U.S. Plans | Mutual funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 148,812 | 97,941 |
Non-U.S. Plans | Mutual funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Mutual funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 148,812 | 97,941 |
Non-U.S. Plans | Mutual funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Mutual funds | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 |  |
Non-U.S. Plans | Hedge funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 137,356 | 143,833 |
Non-U.S. Plans | Hedge funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Hedge funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 0 | 0 |
Non-U.S. Plans | Hedge funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | 130,200 | 135,786 | $ 303,729
Non-U.S. Plans | Hedge funds | Investments measured at Net Asset Value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets at the end of the year | $ 7,156 | $ 8,047 |

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