Fair Value Measurements (Details) - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|---|
| Fair Value on Non-Recurring Basis | |||
| Fair value assets level 1 to 2 transfers | $ 0 | $ 0 | $ 0 |
| Fair value assets level 2 to 1 transfers | 0 | 0 | 0 |
| Fair value liabilities level 1 to 2 transfers | 0 | 0 | 0 |
| Fair value liabilities level 2 to 1 transfers | $ 0 | $ 0 | $ 0 |
| X | ||||||||||
- 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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| X | ||||||||||
- 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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| X | ||||||||||
- Definition Amount of transfers of liabilities 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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| X | ||||||||||
- Definition Amount of transfers of liabilities 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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| X | ||||||||||
- References No definition available.
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