Pension and Other Postretirement Benefit Plans - Summary of Changes in the Fair Value of Plans' Level 3 Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 28, 2018	Sep. 29, 2017
U.S. Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	$ 147,788	$ 142,464
Effect of exchange rate changes	0	0
Fair value of plan assets at the end of the year	390,829	147,788
U.S. Plans \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	6,176
Fair value of plan assets at the end of the year	0	6,176
U.S. Plans \| Real estate investments \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	0	3,477
Purchases, sales, and settlements		(3,477)
Realized and unrealized gains		0
Fair value of plan assets at the end of the year		0
U.S. Plans \| Hedge funds
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	6,176
Fair value of plan assets at the end of the year	28	6,176
U.S. Plans \| Hedge funds \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	6,176	5,715
Purchases, sales, and settlements	(6,176)	(557)
Realized and unrealized gains	0	1,018
Fair value of plan assets at the end of the year	0	6,176
Non-U.S. Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	1,076,928	1,003,911
Effect of exchange rate changes	(9,778)	75,409
Fair value of plan assets at the end of the year	1,867,481	1,076,928
Non-U.S. Plans \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	437,056
Fair value of plan assets at the end of the year	331,155	437,056
Non-U.S. Plans \| Real estate investments
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	58,974
Fair value of plan assets at the end of the year	144,142	58,974
Non-U.S. Plans \| Real estate investments \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	58,974	55,665
Purchases, sales, and settlements	42,711	(1,199)
Realized and unrealized gains	(784)	2,642
Transfers	0	0
Effect of exchange rate changes	(1,314)	1,866
Fair value of plan assets at the end of the year	99,587	58,974
Non-U.S. Plans \| Insurance contracts
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	74,353
Fair value of plan assets at the end of the year	99,970	74,353
Non-U.S. Plans \| Insurance contracts \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	74,353	39,473
Purchases, sales, and settlements	21,626	422
Realized and unrealized gains	1,551	(7,572)
Transfers	0	40,031
Effect of exchange rate changes	(1,748)	1,999
Fair value of plan assets at the end of the year	95,782	74,353
Non-U.S. Plans \| Hedge funds
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the end of the year	143,833
Non-U.S. Plans \| Hedge funds \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at the beginning of the year	303,729	272,517
Purchases, sales, and settlements	(154,446)	(9,022)
Realized and unrealized gains	(6,650)	19,662
Transfers	0	11,758
Effect of exchange rate changes	(6,847)	8,814
Fair value of plan assets at the end of the year	$ 135,786	$ 303,729

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets still held.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(iv)(02)(A)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount of increase (decrease) in plan assets of defined benefit plan from assets transferred into (from) plan.

+ References

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from purchases, sales and settlements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(iv)(02)(B)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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