Goodwill and Intangible Assets - Changes in Carrying Value of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Beginning balance	$ 186,095	$ 188,169	$ 186,805
Goodwill acquired	132,371
Impact of foreign currency translation	17	(2,074)	1,364
Ending balance	318,483	186,095	188,169
Warehouse
Goodwill [Roll Forward]
Beginning balance	170,896	172,554	171,582
Goodwill acquired	130,919
Impact of foreign currency translation	9	(1,658)	972
Ending balance	301,824	170,896	172,554
Third-party managed
Goodwill [Roll Forward]
Beginning balance	2,890	3,064	3,056
Goodwill acquired	0
Impact of foreign currency translation	(8)	(174)	8
Ending balance	2,882	2,890	3,064
Transportation
Goodwill [Roll Forward]
Beginning balance	12,309	12,551	12,167
Goodwill acquired	1,452
Impact of foreign currency translation	16	(242)	384
Ending balance	$ 13,777	$ 12,309	$ 12,551

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
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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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

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-Topic 350
-SubTopic 20
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-Paragraph 1
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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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