Stockholders' Equity - June 2018 Registered Offering of Common Stock (Details) - Common stock - Goldman Sachs & Co. LLC - Underwriting Agreement $ / shares in Units, $ in Millions	1 Months Ended
Jun. 30, 2018 USD ($) $ / shares shares
Registered Offering
Stockholders' Equity (Deficit)
Number of shares sold by the entity	1,079,580
Issue price of stock \| $ / shares	$ 305.00
Net proceeds after deducting commissions and other transactions costs \| $	$ 311.8
Additional Shares
Stockholders' Equity (Deficit)
Number of shares sold by the entity	95,973

Number of new stock issued during the period.

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