Goodwill (Details) $ in Thousands	6 Months Ended
Jun. 30, 2021 USD ($)
Goodwill [Roll Forward]
Beginning balances	$ 431,477
Acquisitions	122,748
Purchase accounting adjustments	(4,234)
Ending balance	549,991
Title
Goodwill [Roll Forward]
Beginning balances	361,433
Acquisitions	102,546
Purchase accounting adjustments	(4,492)
Ending balance	459,487
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
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-SubTopic 210
-Section S99
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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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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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

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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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