Fair Value Measurements - Summary of Changes In Estimated Fair Value of Level 3 Financial Assets (Details) - Level 3 $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value of long-term equity securities at contract inception	$ 955
Change in fair value	(608)
Balance at September 30, 2018	$ 347

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

Amount of increase (decrease) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Fair value measurement with unobservable inputs reconciliation recurring basis asset long term securities at contract inception.

+ References

No definition available.

+ Details

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