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CONTINGENT LIABILITIES AND OTHER MATTERS (Details) R in Millions			6 Months Ended
	Jul. 23, 2020 USD ($) dispute	Jul. 23, 2020 ZAR (R)	Jun. 27, 2020 USD ($) corporate_entity project	Jun. 29, 2019 USD ($)	Jun. 27, 2020 ZAR (R)	Dec. 31, 2019 USD ($)	Jul. 31, 2019 USD ($)	Jul. 31, 2019 ZAR (R)	Feb. 26, 2019 USD ($)	Feb. 26, 2019 ZAR (R)
Contingent Liabilities and Other Matters
Carrying values of accruals			$ 565,000,000.0			$ 592,400,000
Liability for asbestos product liability matters			525,000,000.0			552,200,000
Insurance recoveries			16,300,000	$ 26,600,000
Payments for asbestos-related matters, net of insurance recoveries			$ 11,800,000	$ 6,300,000
Number of large power projects \| project			2
SOUTH AFRICA \| Large Power Projects
Contingent Liabilities and Other Matters
Gain contingency			$ 65,100,000		R 1,133.3
Estimate of possible legal claim deemed unlikely									$ 54,400,000	R 948.0
SOUTH AFRICA \| Large Power Projects \| Subsequent Event
Contingent Liabilities and Other Matters
Number of disputes \| dispute	9
SOUTH AFRICA \| Large Power Projects \| Demand Bonds
Contingent Liabilities and Other Matters
Bonds issued			52,400,000
SOUTH AFRICA \| Large Power Projects \| Demand Bonds \| Subsequent Event
Contingent Liabilities and Other Matters
Bonds issued	$ 2,300,000
SOUTH AFRICA \| Large Power Projects \| Demand Bonds \| Subsequent Event \| MHPSA
Contingent Liabilities and Other Matters
Litigation settlement	1,100,000	R 18.4
SOUTH AFRICA \| Large Power Projects \| Demand Bonds \| Subsequent Event \| Bonds Upon Completion Of Certain Administrative Milestones
Contingent Liabilities and Other Matters
Bonds issued	$ 3,900,000
SOUTH AFRICA \| Large Power Projects \| Demand Bonds, Stringent Payment Requirements
Contingent Liabilities and Other Matters
Bonds issued			18,800,000
SOUTH AFRICA \| Large Power Projects \| MHPSA April And July 2019 Claims
Contingent Liabilities and Other Matters
Estimate of possible legal claim deemed unlikely							$ 23,400,000	R 407.2
SOUTH AFRICA \| Large Power Projects \| MHPSA Additional Claims
Contingent Liabilities and Other Matters
Estimate of possible legal claim deemed unlikely			10,100,000		R 176.2
Other Long Term Liabilities
Contingent Liabilities and Other Matters
Accruals included in other long-term liabilities			491,600,000			517,600,000
Asbestos Issue
Contingent Liabilities and Other Matters
Loss contingency receivable			496,400,000			509,600,000
Asbestos Issue \| Other Assets
Contingent Liabilities and Other Matters
Insurance recovery assets			$ 446,400,000			$ 459,600,000
Minimum \| Asbestos Issue
Contingent Liabilities and Other Matters
Number of corporate entities named as defendants \| corporate_entity			50