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Leases - Additional Information (Detail) $ in Thousands |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 01, 2021 USD ($) Option | Mar. 31, 2021 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Lessee Lease Description [Line Items] |  |  |  |  |
Finance lease right-of-use assets |  |  | $ 761 | $ 29,606 |
Finance lease liability |  |  | 14 |  |
Operating lease right-of-use assets |  |  | 91,112 | 2,043 |
Operating lease liability |  |  | 99,720 |  |
Cash payment related to lease |  |  | $ 10,022 | 951 | $ 914
Minimum [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, operating lease, lease term |  |  | 1 year |  |
Maximum [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, operating lease, lease term |  |  | 5 years |  |
Office Spaces |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, operating lease, expiration period |  |  | 2023 |  |
Office Equipment [Member] | Minimum [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, operating lease, lease term |  |  | 1 year |  |
Office Equipment [Member] | Maximum [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, operating lease, lease term |  |  | 5 years |  |
ASC 842 [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Finance lease right-of-use assets |  |  | $ 24,654 | 0 | 0
Operating lease right-of-use assets |  |  | $ 93,222 | $ 0 | $ 0
Shorenstein Properties LLC [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, finance lease, initial lease term |  |  | 15 years |  |
Lessee, finance lease, expiration period |  |  | 2023 |  |
Shorenstein Properties LLC [Member] | Lease Amendment [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, finance lease, option to extend the additional lease term | 5 years |  |  |  |
Lessee, finance lease, additional lease expiration period | 2028 |  |  |  |
Percentage increases on each anniversary of rent commencement date 2023 | 2.00% |  |  |  |
Lessee, finance lease, existence of option to extend | true |  |  |  |
Lessee, finance lease, option to extend | Under the terms of the Lease Amendment, the Company has two optional rights to each extend the lease for an additional five years. |  |  |  |
Optional rights to extend lease | Option | 2 |  |  |  |
Rent increase commencement year first option | 2023 |  |  |  |
Percentage increases on each anniversary of rent commencement date 2028 | 3.00% |  |  |  |
Rent increase commencement year second option | 2028 |  |  |  |
Shorenstein Properties LLC [Member] | Lease Amendment [Member] | ASC 842 [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Finance lease right-of-use assets | $ 24,600 |  |  |  |
Finance lease liability | 32,600 |  |  |  |
Operating lease right-of-use assets | 93,200 |  |  |  |
Operating lease liability | $ 101,200 |  |  |  |
Cash payment related to lease |  |  | $ 7,900 |  |
Beijing Economic-Technological Development Area [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Operating lease right-of-use assets |  | $ 3,400 |  |  |
Operating lease liability |  | $ 3,400 |  |  |
Lessee, operating lease, lease term |  | 5 years |  |  |
Lessee, operating lease, expiration period |  | 2026 |  |  |

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