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

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
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-Name Accounting Standards Codification
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-Section 50
-Paragraph 1A
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-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
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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

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- Definition

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

+ References

+ Details

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- 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

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Balance Type:	credit
Period Type:	duration

- Definition

The minimum commitments or obligations by the company that would require the Company to maintain certain EBITDA ratios under the revolver commitments.

+ References

No definition available.

+ Details

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

Maximum borrowing capacity under the letters of credit without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The maximum amount of additional commitments that subject to the satisfaction of certain condition.

+ References

No definition available.

+ Details

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

The minimum aggregate borrowing base that would require the Company to maintain certain EBITDA ratios under the revolver commitments.

+ References

No definition available.

+ Details

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

- Definition

Under the revolver commitments, the required ratio of EBITDA minus certain capital expenditures and cash taxes paid to fixed charges.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility covenant terms monetary.

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No definition available.

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

The percentage of aggregate borrowing base applied to revolver commitments in a line of credit.

+ References

No definition available.

+ Details

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- Definition

The percentage of covenants applied to revolver commitments in a line of credit.

+ References

No definition available.

+ Details

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Namespace Prefix:	zeus_
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Balance Type:	na
Period Type:	duration

- Definition

The maximum first in, last out revolving credit facility pursuant the loan agreement.

+ References

No definition available.

+ Details

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

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Note 7 - Debt (Details Textual) $ in Millions			3 Months Ended	12 Months Ended
Note 7 - Debt (Details Textual) $ in Millions	Dec. 14, 2020 USD ($)	Jan. 10, 2019 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Industrial Revenue Bond Member [Member]
Repayments of Long-term Debt, Total			$ 0.8	$ 0.9
Interest Rate Swap [Member]
Debt Instrument, Term (Year)		5 years
Derivative, Notional Amount		$ 75.0
Derivative, Fixed Interest Rate		2.57%
ABL Credit Facility [Member]
Derivative, Term of Contract (Year)			5 years
Asset Based Revolving Credit Facility Due December 8, 2022 [Member] \| ABL Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 445.0
Letters of Credit, Maximum Borrowing Capacity	20.0
Maximum First In, Last Out Revolving Credit Facility	30.0
Line of Credit Facility, Additional Commitments, Maximum	200.0
Line of Credit Facility, Current Borrowing Capacity	475.0
Line Of Credit Facility Covenant Terms Monetary	$ 30.0
Line of Credit Facility Covenant Terms Percentage of Revolver Commitments	10.00%
Balance Required for Compliance with Revolver Commitments			$ 47.5
Line of Credit Facility Covenant Terms Percentage of Aggregate Borrowing Base	10.00%
Line of Credit Facility Covenant Terms Aggregate Borrowing Base			$ 35.8
Line of Credit Facility Covenant Terms EBITDA Ratio			1.00
Line of Credit Facility, Remaining Borrowing Capacity			$ 162.0
Asset Based Revolving Credit Facility Due December 8, 2022 [Member] \| ABL Credit Facility [Member] \| Base Rate [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate			0.00%
Asset Based Revolving Credit Facility Due December 8, 2022 [Member] \| ABL Credit Facility [Member] \| Base Rate [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate			0.25%
Asset Based Revolving Credit Facility Due December 8, 2022 [Member] \| ABL Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate			1.25%
Asset Based Revolving Credit Facility Due December 8, 2022 [Member] \| ABL Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate			2.75%