Cleveland-Cliffs Inc. Quarterly report pursuant to Section 13 or 15(d)

RELATED PARTIES (Summary of Balance Sheet Presentation) (Details)

v3.8.0.1

RELATED PARTIES (Summary of Balance Sheet Presentation) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Partnership distribution payable	$ 44.2	$ 44.2	$ 44.2
Related Party Transaction, Due from (to) Related Party	11.4		8.1
Trade Accounts Receivable [Member]
Related Party Transaction [Line Items]
Due from Related Parties, Current	7.9		68.1
Derivative [Member]
Related Party Transaction [Line Items]
Due from Related Parties, Current	91.3		37.9
Due to Related Parties, Current	(42.0)		(41.4)
Accounts Payable [Member]
Related Party Transaction [Line Items]
Due to Related Parties, Current	(1.2)		0.0
Other Current Liabilities [Member]
Related Party Transaction [Line Items]
Due to Related Parties, Current	$ (0.4)		$ (12.3)

- Definition

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(11))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
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-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- Definition

Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

+ 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

Amount of borrowings from a creditor other than a bank with a maturity within one year or operating cycle, if longer.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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