Pensions and Other Benefits - Additional Information (Details)						12 Months Ended
	Nov. 08, 2021 USD ($) Employee	Jan. 01, 2021 USD ($)	Jan. 01, 2020 USD ($)	Jan. 01, 2019 USD ($)	Nov. 13, 2018 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2009	Feb. 29, 2020 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Portion of employees included In multiemployer plan							75.00%
Portion of represented employees covered by SPT							67.00%
Collective bargaining agreement term					4 years
Increase to defined benefit plan pension liability due to 2018 labor agreements					$ 26,000,000
Discount rate used for calculating benefit obligation							2.87%	2.54%
Defined benefit plans, accumulated benefit obligation							$ 5,274,000,000	$ 5,979,000,000
Portion of costs for retiree health benefits limited to a per capital dollar maximum							75.00%
Defined Contribution Plan, Eligible Amount Contributed Per Hour		$ 0.65	$ 0.60	$ 0.55			$ 0.50
Net periodic benefit cost, other postretirement benefit plans							$ 17,000,000	$ 20,000,000
UPI
Defined Benefit Plan Disclosure [Line Items]
Ownership interest											50.00%
Forecast
Defined Benefit Plan Disclosure [Line Items]
Future projected benefit cost, other postretirement benefit plans						$ 15,000,000
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rate used for calculating benefit obligation							3.01%	2.72%	3.35%
Expected annual return on plan assets							6.82%	6.47%	6.50%
Pension Benefits | UPI
Defined Benefit Plan Disclosure [Line Items]
Benefit liability											$ 8,000,000
Pension Benefits | United States Steel Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Target allocation for plan assets							50.00%
Pension Benefits | UPI Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Target allocation for plan assets							60.00%
Pension Benefits | Banner Life Insurance Company, William Penn Life Insurance Company of New York, and State Street Global Advisors Trust Company
Defined Benefit Plan Disclosure [Line Items]
Benefit liability	$ 284,000,000
Number of retirees and beneficiaries | Employee	17,800
Pension settlement charge recognized	$ 93,000,000
Pension Benefits | Forecast
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plans, expected net periodic benefit cost						$ (7,000,000)
Pension Benefits | Forecast | United States Steel Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Expected annual return on plan assets						6.90%
Pension Benefits | Forecast | UPI Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Expected annual return on plan assets						5.35%
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rate used for calculating benefit obligation							3.11%	2.80%	3.43%
Target allocation for plan assets							72.00%
Expected annual return on plan assets							4.25%	4.25%	4.25%
Other Benefits | UPI
Defined Benefit Plan Disclosure [Line Items]
Benefit liability											$ 55,000,000
Other Benefits | Forecast
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plans, expected net periodic benefit cost						$ (114,000,000)
Expected annual return on plan assets						4.50%
Steelworkers Pension Trust
Defined Benefit Plan Disclosure [Line Items]
Employer contribution amount for each employee hour worked		$ 3.50						$ 3.35
Total amortization period of losses							29 years			15 years
Steelworkers Pension Trust | Forecast
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plans, expected net periodic benefit cost						$ 74,000,000
Unfunded Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Payments for pension benefits							$ 11,000,000	7,000,000	$ 8,000,000
Unfunded Other Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Payments for pension benefits							46,000,000	46,000,000	45,000,000
Defined Contribution Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan expense							$ 20,000,000	10,000,000	23,000,000
Percentage of employee's percentage contributions, matched by employer							100.00%
Percentage of employee's pay matched by employer							6.00%
Defined Contribution Pension Matching Contribution
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan expense							$ 18,000,000	8,000,000	18,000,000
Supplemental Thrift Plan
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan expense							1,000,000	1,000,000	1,000,000
Canadian Hourly Employees Savings Match
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan expense							4,000,000	4,000,000	$ 3,000,000
Other Postemployment Benefit
Defined Benefit Plan Disclosure [Line Items]
Accrued employee benefits							$ 110,000,000	$ 115,000,000
Minimum | Steelworkers Pension Trust
Defined Benefit Plan Disclosure [Line Items]
Proportion of single plan contribution as to total combined contribution							5.00%	5.00%	5.00%