Fair Value Measurements - Additional Information (Detail) |
Dec. 31, 2017
USD ($)
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| Fair Value Disclosures [Abstract] | |
| Fair value, assets, level 1 to level 2 transfers, amount | $ 0 |
| Fair value, assets, level 2 to level 1 transfers, amount | $ 0 |
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- Definition Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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