Goodwill and Identifiable Intangible Assets, Net - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2019	Jun. 30, 2020	Dec. 31, 2018
Goodwill
Goodwill	$ 332,447	$ 420,782	$ 235,182
Walker
Goodwill
Percentage of fair values in excess of carrying value of two acquired reporting units	27.00%
Percentage of fair values in excess of carrying value for Walker reporting unit	27.00%	29.00%
Goodwill		$ 96,800

The percentage of fair values in excess of carrying value for reporting unit.

No definition available.

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- Definition

The percentage of fair values in excess of carrying value for two specific reporting units.

+ References

No definition available.

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- Definition

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.

+ References

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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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