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

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- Definition

Debt Instrument, Restrictive Covenant, Maximum Borrowing Capacity, Amount

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- Definition

Debt Instrument, Restrictive Covenant, Maximum Borrowing Capacity, Percentage

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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, Commitment Fee Description, Average Daily Usage, Percent

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- Definition

Line of Credit Facility, Factoring Fee, Percent

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No definition available.

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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

The amount of subsequent adjustments to additional paid in capital for convertible financial instruments where a component of equity and a component of debt are recognized.

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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.

+ References

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.

+ References

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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

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

Amount, after accumulated amortization, of debt discount.

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- Definition

Gross amount of debt extinguished.

+ References

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.

+ References

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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

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- Definition

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

+ References

No definition available.

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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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- Definition

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

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Debt - Narrative (Details)			1 Months Ended	4 Months Ended	12 Months Ended
Debt - Narrative (Details)	Aug. 31, 2017 USD ($) subsidiary	Jun. 18, 2017 subsidiary	Jul. 31, 2017 EUR (€)	Dec. 31, 2017 USD ($) $ / shares	Dec. 31, 2017 USD ($) $ / shares
Debt Instrument [Line Items]
Number of subsidiaries \| subsidiary	4	4
Discount on debt issued				$ 67,937,000	$ 67,937,000
Adjustment to additional paid in capital remeasurement of conversion feature					$ 60,760,000
Reclassification of debt to equity, tax effect				17,044,000
Conversion of convertible notes				43,716,000
Interest paid in kind				$ 3,865,000
5.25% Convertible Notes due December 30, 2019
Debt Instrument [Line Items]
Stated interest rate (as a percent)	5.25%			5.25%	5.25%
Convertible debt				$ 0	$ 0
11.0% Senior Secured Term Loan Credit Facilities due September 14, 2018
Debt Instrument [Line Items]
Debt repaid	$ 49,400,000
Stated interest rate (as a percent)	11.00%			11.00%	11.00%
12.75% Senior Secured Notes due December 15, 2018
Debt Instrument [Line Items]
Stated interest rate (as a percent)	12.75%			12.75%	12.75%
5.00% / 7.00% Convertible Notes due August 31, 2022
Debt Instrument [Line Items]
Convertible debt				$ 168,767,000	$ 168,767,000
5.00% / 7.00% Convertible Notes due August 31, 2022 \| Minimum
Debt Instrument [Line Items]
Stated interest rate (as a percent)				5.00%	5.00%
5.00% / 7.00% Convertible Notes due August 31, 2022 \| Maximum
Debt Instrument [Line Items]
Stated interest rate (as a percent)				7.00%	7.00%
Convertible Debt \| 5.00% / 7.00% Convertible Notes due August 31, 2022
Debt Instrument [Line Items]
Aggregate principal amount				$ 164,902,000	$ 164,902,000
Debt term				5 years
Debt conversion price (in dollars per share) \| $ / shares				$ 3.77	$ 3.77
Principal amount for conversion price calculation				$ 1.00	$ 1.00
Interest paid in kind				$ 3,865,000
Convertible Debt \| 5.00% / 7.00% Convertible Notes due August 31, 2022 \| Minimum
Debt Instrument [Line Items]
Stated interest rate (as a percent)				5.00%	5.00%
Convertible Debt \| 5.00% / 7.00% Convertible Notes due August 31, 2022 \| Maximum
Debt Instrument [Line Items]
Stated interest rate (as a percent)				7.00%	7.00%
Line of Credit \| Floating rate New ABL Credit Facility due February 28, 2022
Debt Instrument [Line Items]
Line of credit capacity	$ 125,000,000
Line of credit				$ 101,047,000	$ 101,047,000
Foreign Line of Credit
Debt Instrument [Line Items]
Line of credit capacity \| €			€ 6,500,000
Eligible accounts receivable (as a percent)			100.00%
Factoring fee (as a percent)			0.16%
Line of credit				5,854,000	$ 5,854,000
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				17,044,000
Conversion of convertible notes				$ 43,716,000
Revolving Credit Facility \| Line of Credit \| Floating rate New ABL 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				50.00%
Interest rate during period (as a percent)				3.95%
Fixed charge ratio				1.0	1.0
Cash liquidity percent (as a percent)				10.00%
Covenant borrowing threshold				$ 9,000,000.0
Revolving Credit Facility \| Line of Credit \| Floating rate New ABL Credit Facility due February 28, 2022 \| Minimum
Debt Instrument [Line Items]
Commitment fee on unused capacity (as a percent)				0.25%
Revolving Credit Facility \| Line of Credit \| Floating rate New ABL Credit Facility due February 28, 2022 \| Maximum
Debt Instrument [Line Items]
Commitment fee on unused capacity (as a percent)				0.375%
A.M. Castle & Co. 2017 Management Incentive Plan \| Restricted Stock \| Second Lien Notes
Debt Instrument [Line Items]
Convertible debt				$ 2,400,000	$ 2,400,000