Debt, Weighted Average Interest Rate after Consideration of Interest Rate Swap

No definition available.

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- Definition

Letter of Credit Maximum Borrowing Amount

+ References

No definition available.

+ Details

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Namespace Prefix:	slgn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Letters Of Credit Fronting Fee

+ References

No definition available.

+ Details

Name:	slgn_LettersOfCreditFrontingFee
Namespace Prefix:	slgn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Letters Of Credit Fronting Fee Percentage

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Uncommitted Additional Borrowing Capacity

+ References

No definition available.

+ Details

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Namespace Prefix:	slgn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Details

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Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 50

-Section 40

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12317-112629

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 50

-Section 40

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12355-112629

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ 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 current and noncurrent portions 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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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- 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

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04.(a))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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Long-Term Debt Credit Facility Agreements (Detail)	0 Months Ended	3 Months Ended	12 Months Ended										12 Months Ended								0 Months Ended		0 Months Ended		0 Months Ended
Long-Term Debt Credit Facility Agreements (Detail)	Jan. 14, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2014 U S Term Loans [Member]	Jan. 14, 2014 U S Term Loans [Member] USD ($)	Dec. 31, 2014 Canadian Term Loans [Member] CAD	Jan. 14, 2014 Canadian Term Loans [Member] CAD	Dec. 31, 2014 Term Loan [Member] USD ($)	Dec. 31, 2014 Euro Term Loans [Member]	Jan. 14, 2014 Euro Term Loans [Member] EUR (€)	Dec. 31, 2014 Term Loan Facility [Member]	Dec. 31, 2013 Term Loan Facility [Member]	Dec. 31, 2012 Term Loan Facility [Member]	Dec. 31, 2014 Revolving Loan [Member] USD ($)	Dec. 31, 2013 Revolving Loan [Member]	Dec. 31, 2012 Revolving Loan [Member]	Jan. 14, 2014 U S Revolving Loans [Member] USD ($)	Jan. 14, 2014 Canadian Revolving Loans [Member] CAD	Jan. 14, 2014 Revolving And Term Loans [Member]	Dec. 31, 2014 Revolving And Term Loans [Member] USD ($)	Jan. 14, 2014 Revolving And Term Loans [Member] Base Rate [Member]	Dec. 31, 2014 Maximum [Member] USD ($)	Jan. 14, 2014 Maximum [Member] Revolving Loan [Member]	Jan. 14, 2014 Minimum [Member] Revolving Loan [Member]
Debt Instrument [Line Items]
Long-term debt, due in the next twelve months			$ 125,130,000							$ 34,600,000
Borrowings outstanding under the credit agreement							365,000,000		70,000,000			220,000,000
Borrowings available under the revolving loan facilities								15,000,000														962,600,000
Repayments of long-term debt			754,834,000us-gaap_RepaymentsOfLongTermDebt	308,257,000us-gaap_RepaymentsOfLongTermDebt	285,932,000us-gaap_RepaymentsOfLongTermDebt
Debt, Weighted Average Interest Rate													1.80%	2.00%	2.20%	1.70%	1.90%	1.70%
Weighted average interest rate after interest rate swap													2.70%	2.70%	2.60%
Line of Credit Facility, Maximum Borrowing Capacity																			985,600,000	15,000,000
Letters of Credit Outstanding, Amount																23,000,000
Additional borrowing capacity			1,250,000,000																					625,000,000
Line of credit facility, margin																					1.50%		0.50%
Line of Credit Facility, Interest Rate at Period End						1.76%		2.80%			1.56%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage																0.25%									0.35%	0.20%
Letter Of Credit Maximum Borrowing Amount																200,000,000
Letters Of Credit Facing Fee	500slgn_LettersOfCreditFrontingFee
Letters Of Credit Facing Fee Percentage	0.25%
Loss on early extinguishment of debt		$ 1,500,000	$ 1,474,000	$ 2,068,000	$ 38,704,000