Debt - Dollar and Euro Term Loans Narratives (Details) - Secured debt - USD ($) $ in Millions	6 Months Ended
Jun. 27, 2020	Jun. 29, 2019
Dollar Term Loan
Debt Instrument
Interest rate during period on debt	3.75%
Quarterly amortization payment rate	0.25%
Quarterly amortization payment on debt	$ 8.7	$ 13.0
Dollar Term Loan \| LIBOR
Debt Instrument
Variable interest rate on debt (percent)	2.75%
Dollar Term Loan \| LIBOR \| Minimum
Debt Instrument
Variable interest rate on debt (percent)	1.00%
Euro Term Loan
Debt Instrument
Interest rate during period on debt	0.00%
Quarterly amortization payment rate	0.25%
Quarterly amortization payment on debt	$ 3.7	$ 5.5
Euro Term Loan \| EURIBOR
Debt Instrument
Variable interest rate on debt (percent)	3.00%
Euro Term Loan \| EURIBOR \| Minimum
Debt Instrument
Variable interest rate on debt (percent)	0.00%

Debt Instrument, Quarterly Amortization Payment Rate

No definition available.

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Namespace Prefix:	gtes_
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Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

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Balance Type:	debit
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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