Reorganization Shares Issued to Debt Holders

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

+ References

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- Definition

Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Glossary Convertible Security
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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

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Share-based Compensation - Narrative (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands			1 Months Ended	4 Months Ended	8 Months Ended	12 Months Ended
	Sep. 01, 2017	Aug. 31, 2017	Sep. 30, 2017	Dec. 31, 2017	Aug. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reorganization shares issued to debt holders (in shares)		2,000
Share based compensation expense				$ 605
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense				$ 4,843		$ 4,843
Weighted average recognition period						2 years 8 months
A.M. Castle & Co. 2017 Management Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum shares issuable under stock plans				3,952		3,952
A.M. Castle & Co. 2017 Management Incentive Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reorganization shares issued to debt holders (in shares)	1,734
Number of shares convertible (in shares)	638
Granted (in dollars per share)			$ 3.14
Second Lien Notes
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense				$ 2,144		$ 2,144
Second Lien Notes \| A.M. Castle & Co. 2017 Management Incentive Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Convertible debt				2,400		2,400
Unrecognized compensation expense				$ 2,044		$ 2,044
Weighted average recognition period			2 years 8 months
Vesting period			3 years
Fair value of debt	$ 2,300
Predecessor
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation expense					$ 630		$ 1,154
Predecessor \| Second Lien Notes
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense							$ 0