Fair Value - Narrative (Details) - Recurring measurement - USD ($) $ in Thousands |
Sep. 30, 2018 |
Dec. 31, 2017 |
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| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Total assets measured at fair value | $ 252,780 | $ 354,553 |
| Level 3 | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Total assets measured at fair value | 0 | 0 |
| Liabilities measured at fair value | $ 0 | $ 0 |
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. 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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- Definition Fair value of financial and nonfinancial obligations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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