SIGNIFICANT ACCOUNTING POLICIES - ADDITIONAL INFORMATION (Details) $ in Millions		3 Months Ended								12 Months Ended
	Feb. 29, 2016	Dec. 31, 2017 USD ($) Country	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segment Country	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Significant Accounting Policies [Line Items]
Total net sales, including precious metal content		$ 1,091.0	$ 1,009.2	$ 992.7	$ 900.5	$ 996.5	$ 954.2	$ 1,022.0	$ 772.6	$ 3,993.4	$ 3,745.3	$ 2,674.3
Company years in innovation and service										130 years
Number of countries in which entity operates | Country		120								120
Cost of inventories determined by LIFO method		$ 12.4				8.6				$ 12.4	8.6
Cost of inventories determined by LIFO method, amount of increase if FIFO method was used		10.6				6.8				10.6	6.8
Foreign currency translation adjustments										386.3	(90.5)	(188.1)
Net exchange gains (losses)										(1.7)	10.2	5.2
Warranty Expense										25.7	25.2	6.0
Warranty Accrual		11.8				11.2				11.8	11.2	3.8
R&D costs included in selling, general and administrative expenses										$ 151.7	128.5	74.9
Number of reportable segments | segment										2
Number of reportable segments | segment										2
Prepaid expenses and other current assets		312.6				206.5				$ 312.6	206.5
Deferred income taxes		718.0				751.7				718.0	751.7
Other noncurrent assets, net		156.1				102.9				156.1	102.9
Income taxes payable		54.2				60.8				54.2	60.8
Excess tax benefit related to employee share-based compensation										20.5
Goodwill impairment		558.0	$ 0.0	1,092.9	$ 0.0					1,650.9	0.0	0.0
(Loss) and Gain on Derivative Financial Instruments Designated as Cash Flow Hedges
Significant Accounting Policies [Line Items]
Foreign currency translation adjustments										(48.5)	15.6
Foreign Currency Translation (Loss) Gain
Significant Accounting Policies [Line Items]
Foreign currency translation adjustments recorded in AOCI net of tax effects										434.5	(109.4)
As Reported Balance
Significant Accounting Policies [Line Items]
Prepaid expenses and other current assets						345.6					345.6
Deferred income taxes						848.6					848.6
Other noncurrent assets, net						64.1					64.1
Income taxes payable						64.2					64.2
Accounting Standards Update 2014-09 | Retained Earnings
Significant Accounting Policies [Line Items]
Cumulative effect adjustment on accounting principle in period of adoption		6.0								6.0
Accounting Standards Update 2015-17 | Classification Adjustment As Revised
Significant Accounting Policies [Line Items]
Prepaid expenses and other current assets				33.0		(139.1)					(139.1)
Deferred income taxes				(28.2)		(96.9)					(96.9)
Other noncurrent assets, net				$ (4.8)		38.8					38.8
Income taxes payable						(3.4)					(3.4)
Accounting Standards Update 2016-09 | Capital in Excess of Par Value
Significant Accounting Policies [Line Items]
Cumulative effect adjustment on accounting principle in period of adoption						1.0					1.0
Segment Reconciling Items
Significant Accounting Policies [Line Items]
Total net sales, including precious metal content										40.5	64.3	92.8
Goodwill impairment										$ 1,650.9	$ 0.0	$ 0.0
Dental Products
Significant Accounting Policies [Line Items]
Percentage of sales, professional dental products										92.00%	92.00%	89.00%
Building
Significant Accounting Policies [Line Items]
Useful life (in years)										40 years
Minimum | Building
Significant Accounting Policies [Line Items]
Useful life (in years)	25 years
Minimum | Machinery and equipment
Significant Accounting Policies [Line Items]
Useful life (in years)	3 years									4 years
Maximum | Building
Significant Accounting Policies [Line Items]
Useful life (in years)	50 years
Maximum | Machinery and equipment
Significant Accounting Policies [Line Items]
Useful life (in years)	10 years									15 years
Trademarks | Maximum
Significant Accounting Policies [Line Items]
Intangible asset, useful life (in years)										20 years
Licensing Agreements | Maximum
Significant Accounting Policies [Line Items]
Intangible asset, useful life (in years)										20 years
Customer relationships | Maximum
Significant Accounting Policies [Line Items]
Intangible asset, useful life (in years)										15 years
Allowance for doubtful accounts
Significant Accounting Policies [Line Items]
Allowance for Sirona opening balance		$ 22.4				$ 22.7				$ 22.4	$ 22.7	$ 10.7	$ 8.8
Allowance for doubtful accounts receivable, write-offs										4.8	2.5
Additions - Charged (Credited) To Costs And Expenses										$ 6.6	$ 9.2	$ 4.3