| Acquisitions (Details Textual) (USD $)In Thousands, unless otherwise specified
 | 12 Months Ended | 0 Months Ended | 3 Months Ended |  |  | 
      
        | Dec. 27, 2014 | Dec. 28, 2013 | Dec. 29, 2012 | Oct. 18, 2012 | Dec. 28, 2013 | Apr. 01, 2013 | Mar. 30, 2013 | 
      
        | Business Acquisition [Line Items] |  |  |  |  |  |  |  | 
      
        | Percentage of Common Stock Purchased |  |  |  |  |  | 60.00%snhy_PurchaseOfRemainingInterestInEquityInvestee |  | 
      
        | Transaction cost arising from acquisition |  |  |  |  |  | $ 1,000us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts |  | 
      
        | Goodwill | 5,141us-gaap_Goodwill | 5,221us-gaap_Goodwill | 4,472us-gaap_Goodwill |  | 5,221us-gaap_Goodwill |  |  | 
      
        | Gross carrying amount | 4,479us-gaap_FiniteLivedIntangibleAssetsGross | 3,404us-gaap_FiniteLivedIntangibleAssetsGross |  |  | 3,404us-gaap_FiniteLivedIntangibleAssetsGross |  |  | 
      
        | Gain on purchase of business | 0us-gaap_BusinessCombinationBargainPurchaseGainRecognizedAmount | 528us-gaap_BusinessCombinationBargainPurchaseGainRecognizedAmount | 0us-gaap_BusinessCombinationBargainPurchaseGainRecognizedAmount |  |  |  |  | 
      
        | Equity method investment, ownership percentage |  |  |  |  |  |  | 40.00%us-gaap_EquityMethodInvestmentOwnershipPercentage | 
      
        | Series of Individually Immaterial Business Acquisitions [Member] |  |  |  |  |  |  |  | 
      
        | Business Acquisition [Line Items] |  |  |  |  |  |  |  | 
      
        | Transaction cost arising from acquisition |  |  |  | 1,458us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts / us-gaap_BusinessAcquisitionAxis
 = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
 |  |  |  | 
      
        | Goodwill |  |  |  | 1,731us-gaap_Goodwill / us-gaap_BusinessAcquisitionAxis
 = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
 |  | 726us-gaap_Goodwill / us-gaap_BusinessAcquisitionAxis
 = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
 |  | 
      
        | Gross carrying amount |  |  |  |  |  | 746us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_BusinessAcquisitionAxis
 = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
 |  | 
      
        | Acquisition-related costs (included in Selling, engineering, and administrative expenses) |  |  |  |  | 12us-gaap_BusinessCombinationAcquisitionRelatedCosts / us-gaap_BusinessAcquisitionAxis
 = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
 |  |  | 
      
        | Gain on purchase of business |  |  |  |  | 528us-gaap_BusinessCombinationBargainPurchaseGainRecognizedAmount / us-gaap_BusinessAcquisitionAxis
 = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
 |  |  | 
      
        | Percentage of sale of component supplier |  |  |  | 80.00%snhy_BusinessAcquisitionRevenuePercentageAttributableToAcquiree / us-gaap_BusinessAcquisitionAxis
 = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
 |  |  |  | 
      
        | Seungwon Solutions Corporation [Member] |  |  |  |  |  |  |  | 
      
        | Business Acquisition [Line Items] |  |  |  |  |  |  |  | 
      
        | Transaction cost arising from acquisition |  |  |  | 80us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts / us-gaap_BusinessAcquisitionAxis
 = snhy_SeungwonSolutionsCorporationMember
 |  |  |  | 
      
        | Trade Name [Member] |  |  |  |  |  |  |  | 
      
        | Business Acquisition [Line Items] |  |  |  |  |  |  |  | 
      
        | Gross carrying amount | 774us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_TradeNamesMember
 | 774us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_TradeNamesMember
 |  |  | 774us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_TradeNamesMember
 |  |  | 
      
        | Finite-lived intangible assets, estimated useful life |  |  |  |  | 1 year |  |  | 
      
        | Trade Name [Member] | Series of Individually Immaterial Business Acquisitions [Member] |  |  |  |  |  |  |  | 
      
        | Business Acquisition [Line Items] |  |  |  |  |  |  |  | 
      
        | Trade name |  |  |  |  |  | 18us-gaap_FiniteLivedTradeNamesGross / us-gaap_BusinessAcquisitionAxis
 = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
 / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_TradeNamesMember
 |  | 
      
        | Noncompete Agreements [Member] |  |  |  |  |  |  |  | 
      
        | Business Acquisition [Line Items] |  |  |  |  |  |  |  | 
      
        | Gross carrying amount | 11us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_NoncompeteAgreementsMember
 | 11us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_NoncompeteAgreementsMember
 |  |  | 11us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_NoncompeteAgreementsMember
 |  |  | 
      
        | Finite-lived intangible assets, estimated useful life |  |  |  |  | 2 years |  |  | 
      
        | Noncompete Agreements [Member] | Series of Individually Immaterial Business Acquisitions [Member] |  |  |  |  |  |  |  | 
      
        | Business Acquisition [Line Items] |  |  |  |  |  |  |  | 
      
        | Non-compete agreements |  |  |  |  |  | 11us-gaap_FiniteLivedNoncompeteAgreementsGross / us-gaap_BusinessAcquisitionAxis
 = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
 / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_NoncompeteAgreementsMember
 |  | 
      
        | Customer Relationships [Member] |  |  |  |  |  |  |  | 
      
        | Business Acquisition [Line Items] |  |  |  |  |  |  |  | 
      
        | Gross carrying amount | 1,751us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_CustomerRelationshipsMember
 | 1,751us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_CustomerRelationshipsMember
 |  |  | 1,751us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_CustomerRelationshipsMember
 |  |  | 
      
        | Customer Relationships [Member] | Series of Individually Immaterial Business Acquisitions [Member] |  |  |  |  |  |  |  | 
      
        | Business Acquisition [Line Items] |  |  |  |  |  |  |  | 
      
        | Finite-lived intangible assets, estimated useful life |  |  |  |  | 15 years |  |  | 
      
        | Customer relationships |  |  |  |  |  | 276us-gaap_FiniteLivedCustomerRelationshipsGross / us-gaap_BusinessAcquisitionAxis
 = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
 / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_CustomerRelationshipsMember
 |  | 
      
        | Developed Technology Rights [Member] | Series of Individually Immaterial Business Acquisitions [Member] |  |  |  |  |  |  |  | 
      
        | Business Acquisition [Line Items] |  |  |  |  |  |  |  | 
      
        | Finite-lived intangible assets, estimated useful life |  |  |  |  | 10 years |  |  | 
      
        | Acquired definite lived intangible assets |  |  |  |  |  | $ 441us-gaap_OtherFiniteLivedIntangibleAssetsGross / us-gaap_BusinessAcquisitionAxis
 = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
 / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis
 = us-gaap_DevelopedTechnologyRightsMember
 |  |