Leases - Additional Information (Detail) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Lessee, Lease, Description [Line Items] | ||||
| Operating lease expense | $ 2.1 | $ 1.7 | $ 5.9 | $ 5.5 |
| Operating Cash Flows From Operating Lease | 1.9 | 1.7 | $ 5.6 | 5.1 |
| Minimum [Member] | ||||
| Lessee, Lease, Description [Line Items] | ||||
| Sublease lease term | 1 year | |||
| Maximum [Member] | ||||
| Lessee, Lease, Description [Line Items] | ||||
| Sublease lease term | 15 years | |||
| Location, Statement of Income, Balance [Axis]: ithuf:InterestAndOtherIncomeExpense | Sublease [Member] | ||||
| Lessee, Lease, Description [Line Items] | ||||
| Sublease Income | $ 0.2 | $ 0.2 | $ 0.6 | $ 0.7 |
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- Definition Operating Cash Flows From Operating Lease No definition available.
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- Definition Sublease lease term. No definition available.
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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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of operating lease expense. Excludes sublease income. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of sublease income excluding finance and operating lease expense. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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