Goodwill - Components of and Changes in Goodwill (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Goodwill [Roll Forward]
Balance as of December 31, 2019	$ 843.7
Additions	82.9
Foreign exchange and other adjustments	(11.1)
Balance as of March 31, 2020	915.4
Aviation
Goodwill [Roll Forward]
Balance as of December 31, 2019	323.6
Additions	82.9
Foreign exchange and other adjustments	(1.4)
Balance as of March 31, 2020	405.1
Land
Goodwill [Roll Forward]
Balance as of December 31, 2019	520.1
Additions	0.0
Foreign exchange and other adjustments	(9.7)
Balance as of March 31, 2020	510.4
Land Reporting Unit \| Land
Goodwill [Roll Forward]
Balance as of March 31, 2020	$ 445.7

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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