Property and Equipment - Additional Information (Detail) - USD ($) |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2018 |
Sep. 30, 2017 |
Dec. 31, 2017 |
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| Property, Plant and Equipment [Line Items] | |||||
| Depreciation, total | $ 3,000,000 | $ 3,100,000 | $ 9,100,000 | $ 9,200,000 | |
| Accumulated depreciation, depletion and amortization, property, plant, and equipment | 167,934,000 | 167,934,000 | $ 164,720,000 | ||
| Capital Lease [Member] | |||||
| Property, Plant and Equipment [Line Items] | |||||
| Depreciation, total | 5,000.0 | $ 24,000.0 | 48,000.0 | $ 70,000.0 | |
| Accumulated depreciation, depletion and amortization, property, plant, and equipment | $ 200,000 | $ 200,000 | $ 800,000 | ||
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- Definition Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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- Details
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