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Amount awarded from other party in judgment or settlement of litigation.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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CONTINGENT LIABILITIES AND OTHER MATTERS - Large Power Projects in South Africa (Details) R in Millions, $ in Millions			3 Months Ended	9 Months Ended
	Jul. 23, 2020 USD ($) dispute	Jul. 23, 2020 ZAR (R)	Sep. 26, 2020 USD ($)	Sep. 26, 2020 USD ($) project	Sep. 26, 2020 ZAR (R)	Dec. 31, 2019 USD ($)	Jul. 31, 2019 USD ($)	Jul. 31, 2019 ZAR (R)	Feb. 26, 2019 USD ($)	Feb. 26, 2019 ZAR (R)
Contingent Liabilities and Other Matters
Number of large power projects \| project				2
Other assets			$ 615.2	$ 615.2		$ 605.9
SOUTH AFRICA \| Large Power Projects
Contingent Liabilities and Other Matters
Gain contingency			66.7	66.7	R 1,133.3
Estimate of possible legal claim deemed unlikely									$ 55.8	R 948.0
Number of disputes \| dispute	9
SOUTH AFRICA \| Large Power Projects \| Demand Bonds
Contingent Liabilities and Other Matters
Original loan balance	$ 2.3
SOUTH AFRICA \| Large Power Projects \| Demand Bonds \| MHI
Contingent Liabilities and Other Matters
Litigation settlement	1.1	R 18.4
Payment for bonds			14.3
Other assets			14.3	14.3
SOUTH AFRICA \| Large Power Projects \| Demand Bonds \| Bonds Upon Completion Of Certain Administrative Milestones
Contingent Liabilities and Other Matters
Original loan balance	$ 4.0
SOUTH AFRICA \| Large Power Projects \| Demand Bonds, Bond Guarantee Only Exercised by MHI \| MHI
Contingent Liabilities and Other Matters
Long-term debt			19.2	19.2
SOUTH AFRICA \| Large Power Projects \| Demand Bonds, Performance and Retention Money Guarantees \| MHI
Contingent Liabilities and Other Matters
Long-term debt			18.1	18.1
SOUTH AFRICA \| Large Power Projects \| MHI April And July 2019 Claims
Contingent Liabilities and Other Matters
Estimate of possible legal claim deemed unlikely							$ 23.9	R 407.2
SOUTH AFRICA \| Large Power Projects \| MHI Additional Claims
Contingent Liabilities and Other Matters
Estimate of possible legal claim deemed unlikely			$ 10.4	$ 10.4	R 176.2