The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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GOODWILL AND OTHER INTANGIBLE ASSETS (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Changes in the carrying amount of goodwill
Beginning goodwill, net	$ 6,383.0
Current year business combinations	534.6
Prior year business combinations	0.3
Effect of foreign currency translation	(29.9)
Ending goodwill, net	6,947.8		$ 6,383.0
Goodwill expected to be tax deductible	4.2
Impairment of goodwill	0.0
Future estimated amortization expense related to amortizable other identifiable intangible assets
Estimated expense remaining for the year	233.0
Total amortization expense related to other intangible assets	73.8	$ 72.6
Previously Reported
Changes in the carrying amount of goodwill
Beginning goodwill, net	6,383.0
Ending goodwill, net			6,383.0
Global Industrial
Changes in the carrying amount of goodwill
Beginning goodwill, net	2,585.0
Current year business combinations	4.2
Effect of foreign currency translation	(11.2)
Ending goodwill, net	2,600.4		2,585.0
Global Industrial \| Previously Reported
Changes in the carrying amount of goodwill
Beginning goodwill, net	2,522.3
Ending goodwill, net			2,522.3
Global Industrial \| Adjustment.
Changes in the carrying amount of goodwill
Reclassifications			62.7
Global Institutional
Changes in the carrying amount of goodwill
Beginning goodwill, net	590.7
Current year business combinations	530.4
Effect of foreign currency translation	(4.8)
Ending goodwill, net	1,125.9		590.7
Global Institutional \| Previously Reported
Changes in the carrying amount of goodwill
Beginning goodwill, net	653.4
Ending goodwill, net			653.4
Global Institutional \| Adjustment.
Changes in the carrying amount of goodwill
Reclassifications			(62.7)
Global Energy
Changes in the carrying amount of goodwill
Beginning goodwill, net	3,093.6
Prior year business combinations	0.3
Effect of foreign currency translation	(13.4)
Ending goodwill, net	3,107.3		3,093.6
Global Energy \| Previously Reported
Changes in the carrying amount of goodwill
Beginning goodwill, net	3,093.6
Ending goodwill, net			3,093.6
Other
Changes in the carrying amount of goodwill
Beginning goodwill, net	113.7
Effect of foreign currency translation	(0.5)
Ending goodwill, net	114.2		113.7
Other \| Previously Reported
Changes in the carrying amount of goodwill
Beginning goodwill, net	$ 113.7
Ending goodwill, net			$ 113.7