COMMITMENTS AND CONTINGENCIES Roll Forward of Asbestos Liability and Related Assets (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Net Asbestos Liability Rollforward [Line Items]
Asbestos Liability And Related Assets Net Current And Noncurrent - Beginning			$ (508.5)	$ (573.7)
Asbestos Related Costs, Provision to Maintain 10-Year Forecast Period	$ 13.4	$ 13.6	39.3	43.4
Asbestos Related (Benefit) Costs, Annual Remeasurement	7.2	(76.4)	7.2	(76.4)
Gain From Asbestos Insurance Settlement Agreement	(24.9)	0.0	(57.0)	0.0
Cash Payments			(42.3)	(39.5)
Asbestos Liability And Related Assets Net Current And Noncurrent - Ending	(455.7)	(501.2)	(455.7)	(501.2)
Asbestos-related liabilities Current	73.3	77.4	73.3	77.4	$ 77.1
Asbestos-related liabilities Non-Current	771.8	798.1	771.8	798.1	800.1
Asbestos-related assets Current	67.1	64.7	67.1	64.7	64.7
Asbestos-related assets Non-Current	322.3	309.6	322.3	309.6	$ 304.0
Liability [Member]
Net Asbestos Liability Rollforward [Line Items]
Asbestos Liability And Related Assets Net Current And Noncurrent - Beginning			(877.2)	(954.3)
Asbestos Related Costs, Provision to Maintain 10-Year Forecast Period			48.5	51.1
Asbestos Related (Benefit) Costs, Annual Remeasurement	(8.6)		(8.6)	(66.4)
Gain From Asbestos Insurance Settlement Agreement			0.0	0.0
Cash Payments			(72.0)	(63.5)
Asbestos Liability And Related Assets Net Current And Noncurrent - Ending	(845.1)	(875.5)	(845.1)	(875.5)
Assets [Member]
Net Asbestos Liability Rollforward [Line Items]
Asbestos Liability And Related Assets Net Current And Noncurrent - Beginning			368.7	380.6
Asbestos Related Costs, Provision to Maintain 10-Year Forecast Period			(9.2)	(7.7)
Asbestos Related (Benefit) Costs, Annual Remeasurement	15.8		15.8	(10.0)
Gain From Asbestos Insurance Settlement Agreement			(57.0)	0.0
Cash Payments			29.7	24.0
Asbestos Liability And Related Assets Net Current And Noncurrent - Ending	$ 389.4	$ 374.3	$ 389.4	$ 374.3

Asbestos Liability and Related Assets Net Current and Noncurrent

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- Definition

Asbestos-related assets include both the probable insurance recoveries for the asbestos liabilities for pending claims, as well as unasserted claims to be filed over the next 10 years.

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- Definition

In the third quarter of each year, we conduct our asbestos remeasurement to review and update the underlying assumptions used in our asbestos liability and related asset estimates and to determine the cost the Company estimates will be incurred to resolve all pending claims, as well as unasserted claims estimated to be filed over the next 10 years. In each remeasurement, the underlying assumptions are updated based on actual experience since the previous annual remeasurement and we reassess the appropriate reference period of years of experience used in determining each assumption and our expectations regarding future conditions, including inflation.

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In addition to the charges associated with our annual measurement, we record a net asbestos charge each quarter to maintain a rolling 10-year forecast period.

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- Definition

During 2013, ITT executed a final settlement agreement (the 2013 Settlement) with an insurer to settle responsibility for multiple categories of insured claims, including pending and future product liability claims. Under the terms of the 2013 Settlement, the insurer agreed to a specified series of payments over the course of the next five years, resulting in a one-time benefit of $31.0.

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- Definition

Asbestos-related current assets.

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- Definition

Asbestos related liability current.

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- Definition

The payments made in the period which reduced asbestos loss contingency reserves, net of associated insurance reimbursements.

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[Line Items] for Net Asbestos Liability Rollforward [Table]

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- Definition

Amount of loss contingency liability expected to be resolved after one year or beyond the normal operating cycle, if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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