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

REVENUE (Narrative) (Details)

v3.19.1

REVENUE (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
REVENUE (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Contract with Customer, Liability, Revenue Recognized			$ 51.4
Other current liabilities	$ 113.4		125.5
Take or Pay Contracts [Member]
Contract with Customer, Liability	5.3		8.2
Not Designated as Hedging Instrument [Member]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	5.5	$ 43.8
Other Current Liabilities [Member]
Contract with Customer, Liability	12.9		12.9
Other Liabilities [Member]
Contract with Customer, Liability, Noncurrent	$ 38.5	$ 51.4	$ 38.5	$ 51.4

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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