Accrued Liabilities - Other - Accrued Liabilities - Other (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Environmental	$ 9,304,000	$ 9,475,000
Warranty	1,183,000us-gaap_ProductWarrantyAccrual	1,176,000us-gaap_ProductWarrantyAccrual
Taxes (other than income) and insurance	718,000sli_TaxesOtherThanIncomeAndInsurance	879,000sli_TaxesOtherThanIncomeAndInsurance
Commissions	677,000us-gaap_AccruedSalesCommissionCurrent	551,000us-gaap_AccruedSalesCommissionCurrent
Foreign currency forward contracts	542,000	673,000
Other professional fees	421,000us-gaap_AccruedProfessionalFeesCurrent	496,000us-gaap_AccruedProfessionalFeesCurrent
Accrued customer incentive plans	411,000	414,000
Deferred compensation - current	265,000	265,000
Litigation and legal fees	115,000sli_AccruedLitigationAndLegalFees	91,000sli_AccruedLitigationAndLegalFees
Acquisition earn-out, current	72,000	32,000
Deferred revenue	53,000us-gaap_DeferredRevenue	44,000us-gaap_DeferredRevenue
Other	2,302,000sli_OtherAccruedLiabilitiesCurrentOther	2,370,000sli_OtherAccruedLiabilitiesCurrentOther
Accrued liabilities - other	$ 16,063,000us-gaap_OtherAccruedLiabilitiesCurrent	$ 16,466,000us-gaap_OtherAccruedLiabilitiesCurrent

Accrued liabilities customer incentives current.

No definition available.

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- Definition

Carrying value as of the balance sheet date of accrued litigation and legal fees.

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Carrying value as of the balance sheet date of the accrued acquisition earn-out. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of other accrued liabilities not otherwise specified. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of accrued taxes (other than income taxes) and accrued insurance.

+ References

No definition available.

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- Definition

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for sales commissions. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Fair value as of the balance sheet date of all foreign currency derivative liabilities not designated as hedging instruments.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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