Goodwill and other intangibles (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($)
Goodwill [Roll Forward]
Beginning balances	$ 431,477
Acquisitions	52,821
Purchase accounting adjustments	(4,139)
Ending balance	480,159
Title
Goodwill [Roll Forward]
Beginning balances	361,433
Acquisitions	32,619
Purchase accounting adjustments	(4,397)
Ending balance	389,655
Ancillary Services and Corporate
Goodwill [Roll Forward]
Beginning balances	70,044
Acquisitions	20,202
Purchase accounting adjustments	258
Ending balance	$ 90,504

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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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Reference 3: 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

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-SubTopic 20
-Section 50
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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
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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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