Portion of the aggregate cash consideration held in escrow to secure the indemnification obligations of the seller.

No definition available.

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- Definition

Number of environmental sites.

+ References

No definition available.

+ Details

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- Definition

Post-closing working capital adjustment.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Date of sale of Company's business segment.

+ References

No definition available.

+ Details

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Namespace Prefix:	sli_
Data Type:	xbrli:dateItemType
Balance Type:	na
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- Definition

Amount of gain (loss), before tax expense or benefit and not previously recognized, resulting from the sale of a business component.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

+ Details

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- Definition

Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

+ References

+ Details

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Discontinued Operations - Additional Information (Detail) (USD $)	0 Months Ended	1 Months Ended	3 Months Ended
	Dec. 31, 2014	Feb. 28, 2015	Mar. 31, 2015	Nov. 17, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of environmental sites			5sli_NumberOfEnvironmentalSites
SL Delaware Holdings [Member] \| RFL [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Purchase Agreement, Transaction Date of Sale			Nov. 17, 2014
Aggregate cash consideration for sale of divested business				$ 20,000,000
Post-closing working capital adjustment received		299,000
Cash consideration held as escrow deposits				2,000,000
Pre-tax gain on sale of business	6,650,000
Gain on sale of business, net of tax	$ 4,322,000