Annual report pursuant to Section 13 and 15(d)

Stock Options, Stock Grants and New Stock (Stock Options by Exercise Price Range) (Details)

v2.4.1.9
Stock Options, Stock Grants and New Stock (Stock Options by Exercise Price Range) (Details) (USD $)
 12 Months Ended
Jan. 03, 2015
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Number of Outstanding options (shares) 157,295us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
Number of exercisable options (shares) 56,787us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
$11.55 [Member]  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices (dollars per share) $ 11.55synl_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePrice
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
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Number of Outstanding options (shares) 82,342us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
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Weighted average exercise price (dollars per share) $ 11.55us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
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Weighted average remaining contractual life in years (years) 6 years 0 months 17 days
Number of exercisable options (shares) 42,342us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
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Exercisable options, weighted average exercise price (dollars per share) $ 11.55us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
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$11.35 [Member]  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices (dollars per share) $ 11.35synl_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePrice
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Number of Outstanding options (shares) 27,996us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
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Weighted average exercise price (dollars per share) $ 11.35us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
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Weighted average remaining contractual life in years (years) 7 years 1 month 1 day
Number of exercisable options (shares) 8,912us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
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Exercisable options, weighted average exercise price (dollars per share) $ 11.35us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
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$13.70 [Member]  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices (dollars per share) $ 13.70synl_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePrice
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
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Number of Outstanding options (shares) 33,167us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
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Weighted average exercise price (dollars per share) $ 13.70us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
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Weighted average remaining contractual life in years (years) 8 years 1 month 1 day
Number of exercisable options (shares) 5,533us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
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Exercisable options, weighted average exercise price (dollars per share) $ 13.70us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1
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$14.76 [Member]  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices (dollars per share) $ 14.76synl_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePrice
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Number of Outstanding options (shares) 13,790us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
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Weighted average exercise price (dollars per share) $ 14.76us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
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Weighted average remaining contractual life in years (years) 9 years 1 month 18 days
Number of exercisable options (shares) 0us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
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