Cleveland-Cliffs Inc. Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 15(d)

Cover
- Cover
- Audit Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Policies)
Notes Tables
Notes Details

PENSIONS AND OTHER POSTRETIREMENT BENEFITS - Multiemployer Plan (Details)

v3.22.0.1

PENSIONS AND OTHER POSTRETIREMENT BENEFITS - Multiemployer Plan (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Multiemployer Plan [Line Items]
Contributions	$ 104	$ 30	$ 4
Steelworkers Pension Trust
Multiemployer Plan [Line Items]
Pension Plan EIN	236648508
Pension Plan Number	499
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending/Implemented	No
Contributions	$ 88	$ 14	4
Surcharge Imposed	No
Total actuarial liability		5,960
Market value of assets		$ 5,998
Funded ratio		1.01
Steelworkers Pension Trust \| Minimum
Multiemployer Plan [Line Items]
Expiration Date of Collective Bargaining Agreement	Sep. 01, 2022
Steelworkers Pension Trust \| Maximum
Multiemployer Plan [Line Items]
Expiration Date of Collective Bargaining Agreement	Sep. 01, 2025
IAM National Pension Fund's National Pension Plan
Multiemployer Plan [Line Items]
Pension Plan EIN	516031295
Pension Plan Number	002
Pension Protection Act Zone Status	Red	Red
FIP/RP Status Pending/Implemented	Implemented
Contributions	$ 16	$ 16	0
Surcharge Imposed	Yes
IAM National Pension Fund's National Pension Plan \| Minimum
Multiemployer Plan [Line Items]
Expiration Date of Collective Bargaining Agreement	May 31, 2022
IAM National Pension Fund's National Pension Plan \| Maximum
Multiemployer Plan [Line Items]
Expiration Date of Collective Bargaining Agreement	May 15, 2023
American Maritime Officers Plan
Multiemployer Plan [Line Items]
Contributions	$ 0	$ 0	$ 0

- Definition

Multiemployer Plan, Pension, Significant, Funded Status Percentage

+ References

No definition available.

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- Definition

Amount of cost for employer contribution to multiemployer plan. Multiemployer plan includes, but is not limited to, pension plan determined to be individually significant and insignificant and other postretirement benefit plan.

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- Definition

Amount of accumulated benefit obligation for multiemployer pension plan determined to be individually significant.

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- Definition

Indicates certified zone status of multiemployer pension plan determined to be individually significant. Acceptable values are "Green", "Yellow", "Orange", "Red", "Other", and "NA".

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Expiration date of collective-bargaining arrangement (CBA) requiring contribution to multiemployer pension plan determined to be individually significant, in YYYY-MM-DD format.

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- Definition

Employer Identification Number (EIN) or Tax Identification Number (TIN) assigned by Internal Revenue Service (IRS) for multiemployer pension plan determined to be individually significant, in nine-digit numeric format.

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- Definition

Indicates whether funding improvement plan or rehabilitation plan was implemented or pending for multiemployer pension plan, determined to be individually significant. Acceptable values are "No", "Pending", "Implemented", "Other", and "NA".

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- Definition

Amount of asset available for benefits to participants in multiemployer pension plan determined to be individually significant.

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Plan number for multiemployer pension plan determined to be individually significant, in three-digit numeric format.

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Indicates whether employer paid surcharge to multiemployer pension plan determined to be individually significant. Acceptable values are "No", "Yes" and "NA".

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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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