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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 liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition 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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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Business Acquisitions (Details 4 ) (USD $) In Millions, unless otherwise specified	3 Months Ended	1 Months Ended
	Mar. 31, 2014	Feb. 28, 2014	Mar. 31, 2015	Dec. 31, 2014
Business Acquisitions
Cash paid for acquisition, net of cash acquired	$ 35.7
Goodwill			484.5us-gaap_Goodwill	484.5us-gaap_Goodwill
Spatial Energy
Business Acquisitions
Cash paid for acquisition, net of cash acquired		35.7
Goodwill associated with acquisition that is deductible for income tax purposes		19.0
Identifiable intangible assets:		13.9
Liabilities accrued in consideration for business acquisition		3.9
Goodwill		$ 25.7