Acquisitions - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Acquisitions
Goodwill	$ 915.4	$ 843.7
Universal Weather And Aviation, Inc.
Acquisitions
Goodwill	82.9
Goodwill, expected to be tax deductible	73.5
Identifiable intangible assets acquired	$ 44.3

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

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-Publisher FASB
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- References

No definition available.

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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