Goodwill - Summary of Changes to Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended |
|---|---|---|
Mar. 31, 2019 |
Dec. 31, 2018 |
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| Goodwill [Line Items] | ||
| Beginning, Gross balance | $ 42,583 | $ 42,583 |
| Beginning, Accumulated impairment losses | (17,415) | (17,415) |
| Beginning, Net balance | 25,168 | 25,168 |
| Ending, Gross balance | 44,767 | 42,583 |
| Ending, Accumulated impairment losses | (17,415) | (17,415) |
| Ending, Net balance | 27,352 | 25,168 |
| Neosho | ||
| Goodwill [Line Items] | ||
| Goodwill, Acquisition | $ 2,184 | $ 0 |
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- Definition Amount after accumulated impairment loss of 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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before accumulated impairment loss of 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
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- Definition 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
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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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