Equity Investments	12 Months Ended
Dec. 31, 2021
Equity Method Investments And Joint Ventures [Abstract]
Equity Investments	9. Equity Investments The carrying value of our equity investments in domestic and foreign companies was $624.6 million at December 31, 2021 ($520.0 million at December 31, 2020), and is recorded in other assets in the consolidated balance sheets. NuMit Nucor owns a 50% economic and voting interest in NuMit LLC (“NuMit”). NuMit owns 100% of the equity interest in Steel Technologies LLC, an operator of 30 sheet processing facilities located throughout the United States, Canada and Mexico. Nucor accounts for its investment in NuMit (on a one-month lag basis) under the equity method, as control and risk of loss are shared equally between the members of NuMit. Nucor’s investment in NuMit was $418.7 million at December 31, 2021 ($323.6 million at December 31, 2020). Nucor received distributions of $0.2 million, $9.5 million and $36.5 million from NuMit during 2021, 2020 and 2019, respectively. Nucor-JFE Nucor owns a 50% economic and voting interest in Nucor-JFE Steel Mexico, S. de R.L. de C.V. (“Nucor-JFE”), a 50-50 joint venture with JFE Steel Corporation (“JFE”) of Japan, to build and operate a galvanized sheet steel plant in central Mexico. After delays caused by the COVID-19 pandemic, Nucor- JFE resumed hot commissioning in early December 2020. Nucor accounts for its investment in Nucor-JFE (on a one-month lag basis) under the equity method, as control and risk of loss are shared equally between the members of Nucor-JFE. Nucor’s investment in Nucor-JFE was $147.0 million at December 31, 2021 ($147.1 million at December 31, 2020). On January 16, 2019, Nucor entered into an agreement to guarantee a percentage, equal to its ownership percentage (50%), of Nucor-JFE’s borrowings under the General Financing Agreement and Promissory Note (the “JFE Facility”). The fair value of the guarantee is immaterial. Nucor’s guarantee expires on April 30, 2022. The maximum amount Nucor-JFE could borrow under the JFE Facility was amended on November 30, 2021 to $100.0 million. The JFE Facility is uncommitted. As of December 31, 2021, there was $90.0 million outstanding under the JFE Facility ($50.0 million as of December 31, 2020). If Nucor-JFE fails to pay when due any amounts for which it is obligated under the JFE Facility, Nucor could be required to pay 50% of such amounts pursuant to and in accordance with the terms of its guarantee. Nucor has not recorded any liability associated with this guarantee. Nucor-JFE has other credit facilities that Nucor has agreed to guarantee. The principal amount subject to guarantee by Nucor for these other credit facilities was $50.0 million as of December 31, 2021 ($25.0 million as of December 31, 2020). The fair value of the guarantees is immaterial. If Nucor-JFE fails to pay when due any amounts for which it is obligated under the other credit facilities, Nucor could be required to pay such amounts pursuant to and in accordance with the terms of its guarantees. Nucor has not recorded any liability associated with these guarantees. Duferdofin Nucor Nucor previously owned a 50% interest in Duferdofin Nucor S.r.l. (“Duferdofin Nucor”), an Italian steel manufacturer, and accounted for its investment (on a one-month lag basis) under the equity method, as control and risk of loss were shared equally between the members of Duferdofin Nucor. In December 2020, Nucor closed on an agreement (the “Duferdofin Agreement”) to transfer its 50% interest in Duferdofin Nucor to the owner of the remaining 50% interest, making Nucor’s investment in Duferdofin Nucor $0 at December 31, 2020. In conjunction with the consummation of the Duferdofin Agreement, Nucor forgave the previously fully reserved, outstanding note receivable of €35.0 million ($37.8 million) from Duferdofin Nucor, and Nucor was released from the guarantee it previously provided with respect to Duferdofin Nucor’s borrowings under Facility A of the Structured Trade Finance Facilities Agreement (the “Duferdofin Agreement”). The fair value of the guarantee was immaterial, and Nucor did not have a liability recorded associated with this guarantee. All Equity Investments Nucor reviews its equity investments for impairment if and when circumstances indicate that a decline in fair value below their carrying amounts may have occurred. Nucor determined that a triggering event occurred in the first quarter of 2020 with respect to its equity method investment in Duferdofin Nucor due to adverse developments in the joint venture’s commercial outlook, which were exacerbated by the COVID-19 pandemic, all of which negatively impacted the joint venture’s strategic direction. After completing its impairment assessment, Nucor determined that the carrying amount exceeded its estimated fair value and the impairment condition was considered to be other than temporary. Therefore, Nucor recorded a $250.0 million impairment charge in the first quarter of 2020. The assumptions that most significantly affected the fair value determination included projected cash flows and the discount rate. The Company-specific inputs for measuring fair value are considered “Level 3” or unobservable inputs that are not corroborated by market data under applicable fair value authoritative guidance, as quoted market prices are not available. Throughout 2020, additional capital contributions were made by the Company to Duferdofin Nucor that were immediately impaired. These additional capital contributions resulted in $5.0 million, $6.6 million and $25.4 million impairment charges against our investment in Duferdofin Nucor in the second, third and fourth quarters of 2020, respectively. Also, in the fourth quarter of 2020, Nucor reclassified into earnings, $158.6 million of cumulative foreign currency translation losses on our investment in Duferdofin Nucor. In 2020, total impairment charges, including the aforementioned note receivable, related to our investment in Duferdofin Nucor were approximately $483.5 million. These non-cash impairment charges are included in the steel mills segment and in losses and impairments of assets in the consolidated statement of earnings for the year ended December 31, 2020.

Equity Investments

12 Months Ended

Dec. 31, 2021

Equity Method Investments And Joint Ventures [Abstract]

9. Equity Investments

The carrying value of our equity investments in domestic and foreign companies was $624.6 million at December 31, 2021 ($520.0 million at December 31, 2020), and is recorded in other assets in the consolidated balance sheets.

NuMit

Nucor owns a 50% economic and voting interest in NuMit LLC (“NuMit”). NuMit owns 100% of the equity interest in Steel Technologies LLC, an operator of 30 sheet processing facilities located throughout the United States, Canada and Mexico. Nucor accounts for its investment in NuMit (on a one-month lag basis) under the equity method, as control and risk of loss are shared equally between the members of NuMit. Nucor’s investment in NuMit was $418.7 million at December 31, 2021 ($323.6 million at December 31, 2020). Nucor received distributions of $0.2 million, $9.5 million and $36.5 million from NuMit during 2021, 2020 and 2019, respectively.

Nucor-JFE

Nucor owns a 50% economic and voting interest in Nucor-JFE Steel Mexico, S. de R.L. de C.V. (“Nucor-JFE”), a 50-50 joint venture with JFE Steel Corporation (“JFE”) of Japan, to build and operate a galvanized sheet steel plant in central Mexico. After delays caused by the COVID-19 pandemic, Nucor- JFE resumed hot commissioning in early December 2020. Nucor accounts for its investment in Nucor-JFE (on a one-month lag basis) under the equity method, as control and risk of loss are shared equally between the members of Nucor-JFE. Nucor’s investment in Nucor-JFE was $147.0 million at December 31, 2021 ($147.1 million at December 31, 2020).

On January 16, 2019, Nucor entered into an agreement to guarantee a percentage, equal to its ownership percentage (50%), of Nucor-JFE’s borrowings under the General Financing Agreement and Promissory Note (the “JFE Facility”). The fair value of the guarantee is immaterial. Nucor’s guarantee expires on April 30, 2022. The maximum amount Nucor-JFE could borrow under the JFE Facility was amended on November 30, 2021 to $100.0 million. The JFE Facility is uncommitted. As of December 31, 2021, there was $90.0 million outstanding under the JFE Facility ($50.0 million as of December 31, 2020). If Nucor-JFE fails to pay when due any amounts for which it is obligated under the JFE Facility, Nucor could be required to pay 50% of such amounts pursuant to and in accordance with the terms of its guarantee. Nucor has not recorded any liability associated with this guarantee.

Nucor-JFE has other credit facilities that Nucor has agreed to guarantee. The principal amount subject to guarantee by Nucor for these other credit facilities was $50.0 million as of December 31, 2021 ($25.0 million as of December 31, 2020). The fair value of the guarantees is immaterial. If Nucor-JFE fails to pay when due any amounts for which it is obligated under the other credit facilities, Nucor could be required to pay such amounts pursuant to and in accordance with the terms of its guarantees. Nucor has not recorded any liability associated with these guarantees.

Duferdofin Nucor

Nucor previously owned a 50% interest in Duferdofin Nucor S.r.l. (“Duferdofin Nucor”), an Italian steel manufacturer, and accounted for its investment (on a one-month lag basis) under the equity method, as control and risk of loss were shared equally between the members of Duferdofin Nucor. In December 2020, Nucor closed on an agreement (the “Duferdofin Agreement”) to transfer its 50% interest in Duferdofin Nucor to the owner of the remaining 50% interest, making Nucor’s investment in Duferdofin Nucor $0 at December 31, 2020.

In conjunction with the consummation of the Duferdofin Agreement, Nucor forgave the previously fully reserved, outstanding note receivable of €35.0 million ($37.8 million) from Duferdofin Nucor, and Nucor was released from the guarantee it previously provided with respect to Duferdofin Nucor’s borrowings under Facility A of the Structured Trade Finance Facilities Agreement (the “Duferdofin Agreement”). The fair value of the guarantee was immaterial, and Nucor did not have a liability recorded associated with this guarantee.

All Equity Investments

Nucor reviews its equity investments for impairment if and when circumstances indicate that a decline in fair value below their carrying amounts may have occurred. Nucor determined that a triggering event occurred in the first quarter of 2020 with respect to its equity method investment in Duferdofin Nucor due to adverse developments in the joint venture’s commercial outlook, which were exacerbated by the COVID-19 pandemic, all of which negatively impacted the joint venture’s strategic direction. After completing its impairment assessment, Nucor determined that the carrying amount exceeded its estimated fair value and the impairment condition was considered to be other than temporary. Therefore, Nucor recorded a $250.0 million impairment charge in the first quarter of 2020. The assumptions that most significantly affected the fair value determination included projected cash flows and the discount rate. The Company-specific inputs for measuring fair value are considered “Level 3” or unobservable inputs that are not corroborated by market data under applicable fair value authoritative guidance, as quoted market prices are not available.

Throughout 2020, additional capital contributions were made by the Company to Duferdofin Nucor that were immediately impaired. These additional capital contributions resulted in $5.0 million, $6.6 million and $25.4 million impairment charges against our investment in Duferdofin Nucor in the second, third and fourth quarters of 2020, respectively. Also, in the fourth quarter of 2020, Nucor reclassified into earnings, $158.6 million of cumulative foreign currency translation losses on our investment in Duferdofin Nucor. In 2020, total impairment charges, including the aforementioned note receivable, related to our investment in Duferdofin Nucor were approximately $483.5 million. These non-cash impairment charges are included in the steel mills segment and in losses and impairments of assets in the consolidated statement of earnings for the year ended December 31, 2020.