Additional credit available subject to pro forma compliance with debt covenant.

No definition available.

Name:	snhy_AdditionalCreditAvailableSubjectToProFormaComplianceWithDebtCovenant
Namespace Prefix:	snhy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of credit facility additional borrowing capacity.

+ References

No definition available.

+ Details

Name:	snhy_LineOfCreditFacilityAdditionalBorrowingCapacity
Namespace Prefix:	snhy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

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
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-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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+ Details

Name:	us-gaap_InterestExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

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

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityPeriodicPayment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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+ Details

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

- Definition

The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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+ Details

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

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=snhy_PNCBankNationalAssociationAsAdministrativeAgentAndLenderPartyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=snhy_ShinhanBankMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=snhy_TermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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Credit Facilities (Details Textual) ₩ in Thousands			6 Months Ended
Credit Facilities (Details Textual) ₩ in Thousands	Apr. 05, 2018 USD ($)	Apr. 01, 2018 USD ($)	Jun. 30, 2018 USD ($)	Jul. 01, 2017 USD ($)	Jun. 30, 2018 KRW (₩)	Mar. 31, 2018 USD ($)	Mar. 30, 2018 KRW (₩)	Dec. 30, 2017 USD ($)
Debt Instrument [Line Items]
Revolving line of credit			$ 256,750,000					$ 116,000,000
PNC Bank, National Association, as Administrative Agent, and Lender Party [Member]
Debt Instrument [Line Items]
Interest expense recognized			4,534,000	$ 1,778,000
PNC Bank, National Association, as Administrative Agent, and Lender Party [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facilities, maximum capacity						$ 300,000,000
Revolving line of credit			256,750,000					116,000,000
Additional credit available subject to pro forma compliance with debt covenant			$ 143,250,000					$ 184,000,000
Interest rate in effect			4.01%		4.01%
Shinhan Bank [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Credit facilities, maximum capacity			$ 897,000		₩ 1,000,000		₩ 1,000,000
Interest rate in effect			2.05%		2.05%
Interest expense recognized			$ 5,000
Loan maturity date			Mar. 31, 2020
Amended Credit Agreement [Member]
Debt Instrument [Line Items]
Credit facilities, maximum capacity		$ 400,000,000
Line of credit facility term loan aggregate principal amount		100,000,000
Accordion feature to increase maximum capacity		$ 200,000,000
Expiration date		Apr. 03, 2023
Amended Credit Agreement [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Cash consideration transferred through revolving credit facility	$ 258,000,000
Amended Credit Agreement [Member] \| PNC Bank, National Association, as Administrative Agent, and Lender Party [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Balance of term loan after net of unamortized debt issuance cost			$ 97,580,000
Amended Credit Agreement [Member] \| Line of Credit Term Loan Payment on July 2, 2018 [Member]
Debt Instrument [Line Items]
Credit facilities, quarterly term loan payment			1,250,000
Amended Credit Agreement [Member] \| Line of Credit Term Loan Payment on July 2020 [Member]
Debt Instrument [Line Items]
Credit facilities, quarterly term loan payment			1,875,000
Amended Credit Agreement [Member] \| Line of Credit Term Loan Payment on July 2022 [Member]
Debt Instrument [Line Items]
Credit facilities, quarterly term loan payment			$ 2,500,000