The increase in the defined benefit obligation related to a 100 basis point decrease in the discount rate.

No definition available.

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- Definition

The increase in the defined benefit obligation related to a 50 basis point decrease in the discount rate.

+ References

No definition available.

+ Details

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Namespace Prefix:	sg_
Data Type:	xbrli:monetaryItemType
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- Definition

The decrease in the defined benefit obligation related to a 50 basis point increase in the discount rate.

+ References

No definition available.

+ Details

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

- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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- 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

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- Details

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Employee benefit plans and compensation plans - Defined benefit plans - Additional information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Sweden
Employee benefit plans and compensation plans
Increase in the defined benefit obligation related to a 100 basis point decrease in the discount rate	$ 2.7
Germany
Employee benefit plans and compensation plans
Increase in the defined benefit obligation related to a 50 basis point decrease in the discount rate	0.7
Decrease in the defined benefit obligation related to a 50 basis point increase in the discount rate	0.6
Defined benefit plans
Employee benefit plans and compensation plans
Accumulated benefit obligation	$ 20.3	$ 17.5	$ 17.4