Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accounting Policies [Abstract]
Fair value assets transferred from level 1 to level 2	$ 0	$ 0	$ 0	$ 0
Fair value assets transferred from level 2 to level 1	0	0	0	0
Fair value liabilities transferred from level 1 to level 2	0	0	0	0
Fair value liabilities transferred from level 2 to level 1	0	0	0	0
Fair value measurement with unobservable inputs reconciliation recurring basis asset transfers net	0	0	0	0
Fair value measurement with unobservable inputs reconciliation recurring basis liabilities transfers net	$ 0	$ 0	$ 0	$ 0

No definition available.

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ 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 (bb)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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+ References

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Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.

+ References

No definition available.

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