Fees paid to Third Party for Sales of Receivables

No definition available.

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Namespace Prefix:	stgw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Profit Interest Award, Liability

+ References

No definition available.

+ Details

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Namespace Prefix:	stgw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Trade Receivables Collected and Due to Third Party under Receivable Purchase Agreement

+ References

No definition available.

+ Details

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Namespace Prefix:	stgw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of decrease from sale of accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 11
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919244-210447

+ Details

Name:	us-gaap_AccountsReceivableSale
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of increase (decrease) in allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of noncash expense for share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=stgw_OtherAwardsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=stgw_StockCompensationAwardMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Supplemental Information (Details) - USD ($) $ in Thousands	3 Months Ended
Supplemental Information (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Share Capital [Line Items]
Stock-based compensation	$ 12,004	$ 8,021
Accounts Receivable, Sale	82,000	7,500
Trade Receivables Collected and Due to Third Party under Receivable Purchase Agreement	2,400		$ 5,700
Trade Receivable Fees paid to Third Party under Receivable Purchase Agreement	1,300	100
Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)	2,100
Stockholders' Equity Attributable to Noncontrolling Interest
Share Capital [Line Items]
Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)	1,200
Other Awards
Share Capital [Line Items]
Profit interest award liability	24,900		$ 21,000
Stock Compensation Award
Share Capital [Line Items]
Stock-based compensation	7,400	7,200
Profit interest
Share Capital [Line Items]
Stock-based compensation	$ 4,600	$ 700