Long-Term Debt - Convertible Senior Notes Due 2026 - Additional Information (Details) - 2.25% Convertible Senior Notes Due 2026	1 Months Ended	9 Months Ended
Feb. 28, 2020 USD ($) TradingDay BusinessDay $ / shares	May 29, 2020 USD ($)
Debt Instrument [Line Items]
Debt instrument, stated interest rate	2.25%
Debt instrument, maturity date	Feb. 15, 2026
Debt instrument, sinking fund provided	$ 0
Debt instrument, convertible, initial conversion rate in ordinary shares	24.6252
Debt instrument, convertible, principal amount considered for conversion rate	$ 1,000	$ 1,000
Debt instrument, convertible, initial conversion price per ordinary share \| $ / shares	$ 40.61
Debt instrument, convertible, terms of conversion feature		The holders of the Notes may convert their Notes at their option in the following circumstances:during any fiscal quarter commencing after the fiscal quarter ending on May 29, 2020 (and only during such fiscal quarter), if the last reported sale price per ordinary share exceeds 130% of the conversion price for each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding fiscal quarter;during the five consecutive business days immediately after any 10 consecutive trading day period (such 10 consecutive trading day period, the measurement period) in which the trading price per $1,000 principal amount of Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price per ordinary share on such trading day and the conversion rate on such trading day; upon the occurrence of certain corporate events or distributions on the Company’s ordinary shares, as provided in the Indenture; if the Company calls such Notes for redemption; and on or after August 15, 2025 until the close of business on the second scheduled trading day immediately before the maturity date.
Debt instrument, convertible, threshold consecutive trading days \| TradingDay	30
Debt instrument, convertible, threshold consecutive business days \| BusinessDay	5
Debt instrument, convertible, measurement period for conversion option	10 days
Debt instrument specified dollar amount		$ 1,000
Debt instrument, combination settlement description		The Company’s intent is to settle conversions through combination settlement with a specified dollar amount of $1,000 per $1,000 principal amount of Notes, which involves repayment of the principal portion of such Notes in cash and any excess of the conversion value over the principal amount in ordinary shares, with cash in lieu of any fractional ordinary shares
Debt instrument, convertible, carrying amount of liability component	$ 197,500,000
Debt instrument, convertible, discount rate used to calculate carrying amount of liability component	6.53%
Debt instrument, convertible, carrying amount of equity component gross	$ 52,500,000
Debt issuance costs and purchaser discount	8,000,000
Debt issuance costs for liability component	6,300,000
Debt issuance costs for equity component	$ 1,700,000	$ 1,700,000
Debt instrument, remaining life of debt		69 months
Debt instrument, effective interest rate		7.06%
Debt instrument, convertible, carrying amount of equity component		$ 50,800,000
Debt instrument, convertible, principal amount of debt considered for estimation of fair value		100
Fair Value Measurement, Inputs, Level 2
Debt Instrument [Line Items]
Debt instrument, convertible, estimated fair value		$ 219,700,000
Redeem from February 21, 2023 before Maturity Date
Debt Instrument [Line Items]
Debt instrument, convertible, threshold trading days \| TradingDay	20
Debt instrument, convertible, threshold consecutive trading days \| TradingDay	30
Minimum
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger	130.00%
Debt instrument, convertible, threshold trading days \| TradingDay	20
Minimum \| Redeem from February 21, 2023 before Maturity Date
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger	130.00%
Maximum
Debt Instrument [Line Items]
Debt instrument, convertible, product percentage of last reported sale price per ordinary share and conversion rate	98.00%
Private Placement
Debt Instrument [Line Items]
Debt instrument, face amount	$ 250,000,000
Debt instrument, stated interest rate	2.25%
Exercise of Option to Purchase Additional Notes by Initial Purchasers \| Private Placement
Debt Instrument [Line Items]
Debt instrument, face amount	$ 30,000,000

Debt instrument, convertible, carrying amount of liability component.

No definition available.

Name:	sgh_DebtInstrumentConvertibleCarryingAmountOfLiabilityComponent
Namespace Prefix:	sgh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument convertible carrying amount of the equity component gross.

+ References

No definition available.

+ Details

Name:	sgh_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponentGross
Namespace Prefix:	sgh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument, convertible, discount rate used to calculate carrying amount of liability component.

+ References

No definition available.

+ Details

Name:	sgh_DebtInstrumentConvertibleDiscountRateUsedToCalculateCarryingAmountOfLiabilityComponent
Namespace Prefix:	sgh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument, convertible, measurement period for conversion option.

+ References

No definition available.

+ Details

Name:	sgh_DebtInstrumentConvertibleMeasurementPeriodForConversionOption
Namespace Prefix:	sgh_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument, convertible, principal amount of debt considered for conversion rate.

+ References

No definition available.

+ Details

Name:	sgh_DebtInstrumentConvertiblePrincipalAmountOfDebtConsideredForConversionRate
Namespace Prefix:	sgh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Debt instrument, convertible, principal amount of debt considered for estimation of fair value.

+ References

No definition available.

+ Details

Name:	sgh_DebtInstrumentConvertiblePrincipalAmountOfDebtConsideredForEstimationOfFairValue
Namespace Prefix:	sgh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Debt instrument, convertible, product percentage of last reported sale price per ordinary share and conversion rate.

+ References

No definition available.

+ Details

Name:	sgh_DebtInstrumentConvertibleProductPercentageOfLastReportedSalePricePerOrdinaryShareAndConversionRate
Namespace Prefix:	sgh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument, convertible, threshold consecutive business days.

+ References

No definition available.

+ Details

Name:	sgh_DebtInstrumentConvertibleThresholdConsecutiveBusinessDays
Namespace Prefix:	sgh_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument specified dollar amount.

+ References

No definition available.

+ Details

Name:	sgh_DebtInstrumentSpecifiedDollarAmount
Namespace Prefix:	sgh_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt issuance costs and purchaser discount.

+ References

No definition available.

+ Details

Name:	sgh_DebtIssuanceCostsAndPurchaserDiscount
Namespace Prefix:	sgh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Debt issuance costs for equity component.

+ References

No definition available.

+ Details

Name:	sgh_DebtIssuanceCostsForEquityComponent
Namespace Prefix:	sgh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Debt issuance costs for liability component.

+ References

No definition available.

+ Details

Name:	sgh_DebtIssuanceCostsForLiabilityComponent
Namespace Prefix:	sgh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

+ References

No definition available.

+ Details

Name:	us-gaap_ConvertibleDebtFairValueDisclosures
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The type of the financial instrument that the original debt is being converted into (for example, new debt, common stock, preferred stock, etc.) in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

+ Details

Name:	us-gaap_DebtConversionConvertedInstrumentType
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

+ Details

Name:	us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031898-161870

+ Details

Name:	us-gaap_DebtInstrumentConvertibleConversionPrice1
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21521-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644

Reference 3: 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)(5))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

Name:	us-gaap_DebtInstrumentConvertibleConversionRatio1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031898-161870

+ Details

Name:	us-gaap_DebtInstrumentConvertibleRemainingDiscountAmortizationPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the conversion terms of a debt instrument which may include the conversion ratio (including all potential conversion ratios if contingently adjustable), type of debt or equity security into which the debt is convertible, the dollars of debt or the number of shares into which the instrument is convertible (or potentially convertible into), the conversion period, any contingencies associated with the conversion terms, and the existence and amount of a beneficial conversion feature.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

Reference 3: 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)(5))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21521-112644

+ Details

Name:	us-gaap_DebtInstrumentConvertibleTermsOfConversionFeature
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

+ Details

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

- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdTradingDays
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ 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=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

Reference 2: 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=114775744&loc=d3e28551-108399

Reference 3: 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=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount paid into a fund, which is used to retire the debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=sgh_TwoPointTwoFivePercentageConvertibleSeniorNotesDueTwoThousandTwentySixMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=us-gaap_PrivatePlacementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtConversionByUniqueDescriptionAxis=sgh_ExerciseOfOptionToPurchaseAdditionalNotesByInitialPurchasersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: