Ownership percentage of existing stockholder group in combined company.

No definition available.

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- Definition

Ratio applied to each share outstanding to effect a stock acquisition.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Details

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- Details

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- Details

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- Details

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Proposed Cleveland-Cliffs Acquisition (Details)	Jun. 30, 2020	Dec. 31, 2019	Dec. 31, 2018
Forecast [Member]
Business Acquisition [Line Items]
Stockholders' Equity, Stock Acquisition, Consideration Ratio	0.40
Cleveland-Cliffs [Domain] \| Forecast [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	68.00%
AK Steel Holding [Domain] \| Forecast [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	32.00%
Senior Notes Due October 2025 [Member]
Business Acquisition [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		6.375%	6.375%
Senior Notes Due March 2027 [Member]
Business Acquisition [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		7.00%	7.00%