Debt Instrument, Convertible, Conversion Rate, Principal Amount of Convertible Notes for Shares, Principal Amount

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- Definition

Debt Instrument, Convertible, Observation Period Trading Days

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- Definition

Debt Instrument, Convertible, Threshold Percentage Of Fundamental Change, Acquisition Of Voting Power

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- Definition

Debt Instrument, Restrictive Covenant, Maximum Borrowing Capacity, Amount

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- Definition

Debt Instrument, Restrictive Covenants, Fixed Charge Coverage Ratio

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- Definition

Line Of Credit Facility, Accounts Receivable Available, Percent

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- Definition

Line Of Credit Facility, Early Redemption Fee, Percent

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- Definition

Line Of Credit Facility, Factoring Fee, Percent

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- Definition

Line of Credit Facility, Commitment Fee Description, Average Daily Usage, Percent

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- Definition

Number of Subsidiaries

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- Definition

Stock Issued During Period, Value, Conversion of Convertible Securities, Tax Effect

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No definition available.

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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

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

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No definition available.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

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

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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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No definition available.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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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.

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No definition available.

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- 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.

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- Definition

The effective interest rate during the reporting period.

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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.

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

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- Definition

Interest paid other than in cash for example by issuing additional debt securities. As a noncash item, it is added to net income when calculating cash provided by or used in operations using the indirect method.

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The gross value of stock issued during the period upon the conversion of convertible securities.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Debt - Narrative (Details)		7 Months Ended	12 Months Ended			16 Months Ended	19 Months Ended	28 Months Ended
Debt - Narrative (Details)	Aug. 31, 2017 USD ($) subsidiary	Dec. 31, 2018 USD ($)	May 31, 2020	Dec. 31, 2019 USD ($) Day	Dec. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 EUR (€)	Dec. 31, 2019 USD ($) $ / shares	Jun. 01, 2018 USD ($)
Debt Instrument [Line Items]
Number of subsidiaries \| subsidiary	4
Unamortized debt issuance costs		$ 422,000			$ 422,000	$ 422,000				$ 289,000
Reclassification of debt to equity, tax effect				$ 1,086,000
Conversion of convertible notes				3,547,000	3,430,000
Noncash interest paid in kind				$ 15,912,000	13,502,000
5.00% / 7.00% Second Lien Notes due August 31, 2022(a)
Debt Instrument [Line Items]
Convertible debt		180,894,000			180,894,000	180,894,000				$ 193,660,000
Redemption Price on Second Lien Notes				100.00%
Noncash interest paid in kind						15,992,000		$ 28,991,000
5.00% / 7.00% Second Lien Notes due August 31, 2022(a) \| Minimum
Debt Instrument [Line Items]
Stated interest rate (as a percent)									5.00%	5.00%
5.00% / 7.00% Second Lien Notes due August 31, 2022(a) \| Maximum
Debt Instrument [Line Items]
Stated interest rate (as a percent)									7.00%	7.00%
Convertible Debt \| 5.00% / 7.00% Second Lien Notes due August 31, 2022(a)
Debt Instrument [Line Items]
Aggregate principal amount	$ 164,902,000
Debt term				5 years
Debt conversion price (in dollars per share) \| $ / shares										$ 3.77
Principal amount for conversion price calculation										$ 1.00
Percentage of voting power acquired by a person or group									50.00%	50.00%
Trading days observation period \| Day				20
Noncash interest paid in kind				$ 12,999,000	12,127,000
Convertible Debt \| 5.00% / 7.00% Second Lien Notes due August 31, 2022(a) \| Minimum
Debt Instrument [Line Items]
Stated interest rate (as a percent)									5.00%	5.00%
Convertible Debt \| 5.00% / 7.00% Second Lien Notes due August 31, 2022(a) \| Maximum
Debt Instrument [Line Items]
Stated interest rate (as a percent)									7.00%	7.00%
Line of Credit \| Floating rate Revolving A Credit Facility due February 28, 2022
Debt Instrument [Line Items]
Line of credit		108,488,000			108,488,000	108,488,000				$ 102,000,000
Line of Credit \| Revolving A Credit Facility \| LIBOR
Debt Instrument [Line Items]
Interest rate margin (as a percent)				3.00%
Line of Credit \| Revolving B Credit Facility
Debt Instrument [Line Items]
Stated interest rate (as a percent)									12.00%	12.00%
Noncash interest paid in kind		1,375,000		$ 2,913,000			$ 4,288,000
Line of credit		22,875,000			22,875,000	22,875,000				$ 25,788,000
Foreign Line of Credit
Debt Instrument [Line Items]
Line of credit capacity \| €									€ 6,500,000
Line of credit		$ 5,498,000			5,498,000	$ 5,498,000				$ 2,888,000
Percent of eligible accounts factored for credit facility borrowing				100.00%
Factoring fee percentage				0.16%
Foreign Line of Credit \| Euribor
Debt Instrument [Line Items]
Interest rate margin (as a percent)				1.00%
Foreign Line of Credit \| LIBOR
Debt Instrument [Line Items]
Interest rate margin (as a percent)				1.00%
Additional Paid-in Capital
Debt Instrument [Line Items]
Reclassification of debt to equity, tax effect					1,208,000
Conversion of convertible notes				$ 3,547,000	$ 3,430,000
Scenario, Forecast \| Line of Credit \| Floating rate Revolving A Credit Facility due February 28, 2022
Debt Instrument [Line Items]
Fee for early termination or payment reduction (as a percentage)			0.25%
Revolving Credit Facility \| Line of Credit \| Floating rate Revolving A Credit Facility due February 28, 2022
Debt Instrument [Line Items]
Line of credit capacity	125,000,000
Commitment fee on unused capacity (as a percent)				0.25%
Average daily revolving facility threshold (as a percent)				50.00%
Interest rate during period (as a percent)				5.32%
Fixed charge ratio									1.0	1.0
Covenant borrowing threshold				$ 12,500,000
Revolving Credit Facility \| Line of Credit \| Floating rate Revolving A Credit Facility due February 28, 2022 \| Maximum
Debt Instrument [Line Items]
Commitment fee on unused capacity (as a percent)				0.375%
Revolving Credit Facility \| Line of Credit \| Revolving B Credit Facility
Debt Instrument [Line Items]
Line of credit capacity											$ 25,000,000
A.M. Castle & Co. 2017 Management Incentive Plan \| Less: unvested restricted Notes
Debt Instrument [Line Items]
Convertible debt	$ 2,400,000									$ 2,300,000