Intangible Franchise Rights and Goodwill - Intangible Franchise Rights by Reportable Segment (Details) $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)
Intangible Franchise Rights [Roll Forward]
Balance	$ 285,632
Additions through acquisitions	19,963
Disposals	(4,872)
Impairments	(22,909)
Currency translation	(1,529)
Balance	276,285
U.S.
Intangible Franchise Rights [Roll Forward]
Balance	255,981
Additions through acquisitions	11,540
Disposals	(4,872)
Impairments	(22,909)
Currency translation	0
Balance	239,740
U.K.
Intangible Franchise Rights [Roll Forward]
Balance	29,483
Additions through acquisitions	8,423
Disposals	0
Impairments	0
Currency translation	(1,498)
Balance	36,408
Brazil
Intangible Franchise Rights [Roll Forward]
Balance	168
Additions through acquisitions	0
Disposals	0
Impairments	0
Currency translation	(31)
Balance	$ 137

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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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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Amount of divestiture of an asset lacking physical substance and having a projected indefinite period of benefit to fair value. Excludes financial assets and goodwill.

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Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, from an acquisition.

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