Annual report pursuant to Section 13 and 15(d)

DEBT AND CREDIT FACILITIES - Debt Redemption (Details)

v3.22.0.1
DEBT AND CREDIT FACILITIES - Debt Redemption (Details)
 12 Months Ended
Dec. 31, 2021
9.875% 2025 Senior Secured Notes | Debt Instrument, Redemption, Period One, Upon Equity Issuance | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 109.875%
9.875% 2025 Senior Secured Notes | Debt Instrument, Redemption, Period One | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00% [1]
9.875% 2025 Senior Secured Notes | Debt Instrument, Redemption, Period Two | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 107.406%
6.750% 2026 Senior Secured Notes | Debt Instrument, Redemption, Period One, Upon Equity Issuance | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 106.75%
6.750% 2026 Senior Secured Notes | Debt Instrument, Redemption, Period One | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00% [1]
6.750% 2026 Senior Secured Notes | Debt Instrument, Redemption, Period Two | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 105.063%
7.000% 2027 Senior Notes | Debt Instrument, Redemption, Period One | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00% [1]
7.000% 2027 Senior Notes | Debt Instrument, Redemption, Period Two | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 103.50%
7.000% 2027 AK Senior Notes | Debt Instrument, Redemption, Period One | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00%
7.000% 2027 AK Senior Notes | Debt Instrument, Redemption, Period Two | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 103.50%
1.500% 2025 Convertible Senior Notes  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00%
5.875% 2027 Senior Notes | Debt Instrument, Redemption, Period One, Upon Equity Issuance | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 105.875%
5.875% 2027 Senior Notes | Debt Instrument, Redemption, Period One | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00% [1]
5.875% 2027 Senior Notes | Debt Instrument, Redemption, Period Two | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 102.938%
6.250% 2040 Senior Notes | Debt Instrument, Redemption, Period One | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00%
4.625% 2029 Senior Notes | Debt Instrument, Redemption, Period One, Upon Equity Issuance | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 104.625%
4.625% 2029 Senior Notes | Debt Instrument, Redemption, Period One | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00% [1]
4.625% 2029 Senior Notes | Debt Instrument, Redemption, Period Two | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 102.313%
4.625% 2029 Senior Notes | Debt Instrument, Redemption, Period Three | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 101.156%
4.625% 2029 Senior Notes | Debt Instrument, Redemption, Period Four | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00%
4.875% 2031 Senior Notes | Debt Instrument, Redemption, Period One, Upon Equity Issuance | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 104.875%
4.875% 2031 Senior Notes | Debt Instrument, Redemption, Period One | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00%
4.875% 2031 Senior Notes | Debt Instrument, Redemption, Period Two | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 102.438%
4.875% 2031 Senior Notes | Debt Instrument, Redemption, Period Three | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 101.625%
4.875% 2031 Senior Notes | Debt Instrument, Redemption, Period Four | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.813%
4.875% 2031 Senior Notes | Debt Instrument, Redemption, Period Five | Cleveland-Cliffs Inc.  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00%
[1] 2 Plus a "make-whole" premium.