Subsequent Events - (Details) - TOPO Research LLC - Subsequent Event $ in Millions	Oct. 01, 2019 USD ($)
Subsequent Event [Line Items]
Percent of outstanding membership interests acquired	100.00%
Purchase price	$ 33

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
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