Commitments and Contingencies - Schedule of Future Minimum Lease Payments under Leases (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Commitments and Contingencies [Line Items]
2020	$ 6,195	$ 6,422
2021	5,192	5,235
2022	3,090	4,189
2023	1,449	2,663
2024 and thereafter	1,386	2,309
Total	17,312	20,818
Rent
Commitments and Contingencies [Line Items]
2020	5,863	6,123
2021	4,865	4,983
2022	2,961	3,957
2023	1,410	2,567
2024 and thereafter	1,385	2,281
Total	16,484	19,911
Office Equipment
Commitments and Contingencies [Line Items]
2020	332	299
2021	327	252
2022	129	232
2023	39	96
2024 and thereafter	1	28
Total	$ 828	$ 907

Commitments and Contingencies [Line Items]

No definition available.

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- Definition

Lessee Operating Lease Liability Payments Due After Year Four

+ References

No definition available.

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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