Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Segment Reporting (Revenues and Other Financial Information by Business Segment) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended								12 Months Ended
	Jan. 31, 2015	Jan. 31, 2017	Oct. 31, 2016	Jul. 31, 2016	Apr. 30, 2016	Jan. 31, 2016	Oct. 31, 2015	Jul. 31, 2015	Apr. 30, 2015	Jan. 31, 2017	Jan. 31, 2016	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 133.0	$ 373.4	$ 389.0	$ 378.9	$ 352.8	$ 358.2	$ 365.0	$ 412.7	$ 431.5	$ 1,494.1	$ 1,567.4	$ 1,695.7
Operating earnings	17.7									129.4	(536.8)	246.8
Total assets	4,224.6	3,698.3				3,691.0				3,698.3	3,691.0	4,280.6
Goodwill	1,286.5	996.4				954.9				996.4	954.9	1,328.7
Capital expenditures	6.2									35.5	130.5	136.8
Depreciation and amortization	7.3									66.9	75.0	68.0
Aerospace Solutions Group
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	93.1									1,340.9	1,312.5	1,310.2
Operating earnings	12.9									220.6	211.6	192.0
Total assets	3,252.2	3,471.4				3,422.8				3,471.4	3,422.8	3,298.4
Goodwill	965.8	996.4				952.4				996.4	952.4	986.3
Capital expenditures	1.7									11.0	30.4	17.7
Depreciation and amortization	2.4									30.4	28.1	28.0
Energy Services Group
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	39.9									153.2	254.9	385.5
Operating earnings	4.8									(91.2)	(748.4)	54.8
Total assets	972.4	226.9				268.2				226.9	268.2	982.2
Goodwill	320.7					2.5					2.5	342.4
Capital expenditures	4.5									24.5	100.1	119.1
Depreciation and amortization	4.9									36.5	46.9	40.0
Corporate, Non-Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Total assets	$ 451.6	$ 378.2				$ 559.5				$ 378.2	$ 559.5	$ 508.4	$ 508.4