Employee Service, Second Lien Note Based, Period For Recognition

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- Definition

Long-Term Debt, Portion Existing Convertible Note Exchanged

+ References

No definition available.

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- Definition

Amount, after tax, of expense for award under share-based payment arrangement.

+ References

No definition available.

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- Definition

The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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Share-based Compensation - Narrative (Details)			6 Months Ended
Share-based Compensation - Narrative (Details)	Mar. 31, 2020 shares	Sep. 01, 2017	Jun. 30, 2020 USD ($) shares	Mar. 27, 2020 USD ($)
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSUs outstanding (in shares) \| shares			783,000
Share based compensation expense			$ 0
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares convertible (in shares) \| shares	1,740,000
Unrecognized compensation expense			$ 202,000
Weighted average recognition period (in years)			8 months 12 days
A.M. Castle & Co. 2017 Management Incentive Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)		3 years
Second Lien Notes \| A.M. Castle & Co. 2017 Management Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense			$ 159,000
Weighted average recognition period (in years)			1 year 8 months 12 days
New Restricted Notes
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate principal amount			$ 793,000
Existing Restricted Notes [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate principal amount of Existing Notes tendered and accepted in exchange				$ 1,613,000
Vesting Upon Achievement of Defined Enterprise Value
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting of share awards (as a percent)			50.00%
Vesting Upon Achievement of the Defined Enterprise Value
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting of share awards (as a percent)			50.00%