Employee Service, Second Lien Note Based, Award Vesting Period

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- Definition

Employee Service, Second Lien Note Based, Period for Recognition

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

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

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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.

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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

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.

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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

The number of grants made 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

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

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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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) $ / shares in Units, shares in Thousands			12 Months Ended
	Apr. 25, 2018	Sep. 01, 2017	Dec. 31, 2019 USD ($) shares $ / shares	Dec. 31, 2018 USD ($) $ / shares	Aug. 31, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation expense			$ 2,862,000	$ 2,784,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense			$ 585,000
Weighted average recognition period			9 months 18 days
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of PSUs outstanding (in shares) \| shares			791
Recognized compensation expense related to PSUs			$ 0
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 (in shares) \| shares			3,952
A.M. Castle & Co. 2017 Management Incentive Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares convertible (in shares) \| shares			610
Cliff vesting period (in years)	1 year	3 years
Unvested grant date fair value (in dollars per share) \| $ / shares			$ 3.13	$ 3.19
Granted (in dollars per share) \| $ / shares			$ 1.77
Performance share unit awards granted (in shares) \| shares			15
Less: unvested restricted Notes \| A.M. Castle & Co. 2017 Management Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Convertible debt			$ 2,300,000		$ 2,400,000
Unrecognized compensation expense			$ 214,000
Second lien note weighted average recognition period			8 months 12 days
Vesting period (in years)			3 years
Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vesting based defined enterprise value			50.00%
Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vesting based defined enterprise value			50.00%