Fair Value Measurements - Additional Information (Detail) - USD ($) |
3 Months Ended | 9 Months Ended | ||
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Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2018 |
Sep. 30, 2017 |
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| Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] | ||||
| Carrying value of notes | $ 245,000,000 | $ 245,000,000 | ||
| Debt instrument, estimated fair value | 221,100,000 | 221,100,000 | ||
| Gain (Loss) on disposition of assets | $ 759,000 | $ (95,000) | (4,400,000) | $ 410,000 |
| KGBIFM [Member] | ||||
| Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] | ||||
| Gain (Loss) on disposition of assets | $ (4,800,000) | |||
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- Definition Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] No definition available.
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Details
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