The number of outstanding shares which are owned by non-controlling shareholders.

No definition available.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

+ Details

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Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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- Details

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- Details

Name:	us-gaap_RelatedPartyTransactionAxis=gdi_LenderMember
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Data Type:	na
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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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Related Party - Narrative (Details) € in Millions, $ in Millions		1 Months Ended	12 Months Ended
	May 31, 2018 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2020 EUR (€) shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 EUR (€)
KKR
Related Party Transaction, Due to Related Party [Abstract]
Expenses with related party				$ 7.5
KKR \| Lender in Senior Secured Credit Facilities \| Euro Term Loan Facility
Related Party Transaction, Due to Related Party [Abstract]
Related party transaction amount \| €			€ 43.3		€ 49.0
KKR \| Lender in Senior Secured Credit Facilities \| Dollar Term Loan B, due 2027
Related Party Transaction, Due to Related Party [Abstract]
Related party transaction amount				$ 39.7
KKR \| Underwriter Discounts and Commissions
Related Party Transaction, Due to Related Party [Abstract]
Related party transaction amount	$ 5.2
KKR \| Services Rendered for Debt Refinancing Transaction
Related Party Transaction, Due to Related Party [Abstract]
Related party transaction amount		$ 0.4
KKR \| Common Stock
Related Party Transaction [Line Items]
Number of shares owned by non-controlling owners (in shares) \| shares			44,788,635	44,788,635
Ownership interest by non-controlling owners (as a percent)			11.00%	11.00%