Goodwill and Other Intangible Assets - Additional Information (Detail) - Consulting [Member] $ in Thousands	6 Months Ended
Jun. 30, 2021 USD ($)
Goodwill [Line Items]
Accumulated goodwill impairment losses	$ 0
Goodwill impairment charges	0
Goodwill allocated to reporting unit	$ 8,300

Amount of accumulated impairment loss for 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 350
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of loss from the write-down 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
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+ References

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Amount of goodwill allocated to reporting unit with zero or negative amount of net assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
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-URI http://asc.fasb.org/extlink&oid=121556970&loc=SL108378252-109267

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