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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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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Goodwill and Intangilble Assets (Goodwill and Amortization Expenses) (Details) - USD ($) $ in Millions	3 Months Ended		5 Months Ended	9 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2016	Oct. 31, 2016	Oct. 31, 2015	Jan. 31, 2016	Dec. 31, 2015
Amortization expense of intangible assets	$ 4.8	$ 5.8		$ 14.7	$ 19.1
Expected amortization expenses in year one	20.0		$ 20.0	20.0
Expected amortization expenses in year two	20.0		20.0	20.0
Expected amortization expenses in year three	20.0		20.0	20.0
Expected amortization expenses in year four	20.0		20.0	20.0
Expected amortization expenses in year five	20.0		20.0	20.0
Goodwill	993.3		993.3	993.3		$ 954.9
Revenues	389.0	365.0		1,148.6	1,209.2
Herndon
Goodwill	44.7		44.7	44.7
Revenues	389.0		56.7
Aerospace Solutions Group
Goodwill increase during period				38.4
Fair value of reporting unit in excess of carrying value (in percentage)							16.00%
Goodwill	993.3		$ 993.3	993.3		$ 952.4
Revenues	$ 348.8	$ 306.7		$ 1,039.0	$ 1,006.4