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CONTINGENT LIABILITIES AND OTHER MATTERS (Details) R in Millions, $ in Millions			3 Months Ended				9 Months Ended
	Oct. 30, 2018 USD ($)	Oct. 30, 2018 ZAR (R)	Sep. 28, 2019 USD ($)	Jun. 29, 2019 USD ($)	Mar. 30, 2019 USD ($)	Sep. 29, 2018 USD ($)	Sep. 28, 2019 USD ($) project corporate_entity	Sep. 29, 2018 USD ($)	Sep. 28, 2019 ZAR (R)	Jul. 31, 2019 USD ($)	Jul. 31, 2019 ZAR (R)	Apr. 30, 2019 USD ($)	Apr. 30, 2019 ZAR (R)	Feb. 26, 2019 USD ($)	Feb. 26, 2019 ZAR (R)	Dec. 31, 2018 USD ($)
Contingent Liabilities and Other Matters
Carrying values of accruals			$ 583.7				$ 583.7									$ 631.7
Liability for asbestos product liability matters			539.9				539.9									587.5
Insurance recoveries							39.1	$ 5.3
Payments for asbestos-related matters, net of insurance recoveries							$ 9.8	26.9
Number of large power projects \| project							2
Revenues			364.8			$ 362.5	$ 1,080.8	1,093.6
All Other
Contingent Liabilities and Other Matters
Revenues			6.0			$ 21.4	(1.1)	$ 81.7
Large Power Projects \| SOUTH AFRICA
Contingent Liabilities and Other Matters
Gain contingency			68.9				68.9		R 1,033.3
Revenues related to claims and unapproved change orders			9.8				9.8
Estimate of possible legal claim deemed unlikely										$ 9.5	R 142.8	$ 17.6	R 264.4	$ 63.2	R 948.0
Other Long Term Liabilities
Contingent Liabilities and Other Matters
Accruals included in other long-term liabilities			556.6				556.6									600.3
Demand Bonds
Contingent Liabilities and Other Matters
Bonds issued			66.1				66.1
Demand Bonds, Stringent Payment Requirements
Contingent Liabilities and Other Matters
Bonds issued			21.8				21.8
Asbestos Issue \| Other Assets
Contingent Liabilities and Other Matters
Insurance recovery assets			$ 502.8				$ 502.8									$ 541.9
DBT Technologies
Contingent Liabilities and Other Matters
Loss contingency, estimate of possible loss	$ 17.1	R 256.0
Minimum \| Asbestos Issue
Contingent Liabilities and Other Matters
Number of corporate entities named as defendants \| corporate_entity							50
Operating Segments \| Large Power Projects \| SOUTH AFRICA \| Contracts Accounted for under Percentage of Completion \| All Other
Contingent Liabilities and Other Matters
Revenues				$ (6.0)	$ (17.5)
Operating Segments \| Alstom/GE \| Large Power Projects \| SOUTH AFRICA \| Contracts Accounted for under Percentage of Completion \| All Other
Contingent Liabilities and Other Matters
Revenues				$ (5.8)