Equity (Details) $ / shares in Units, $ in Millions		9 Months Ended
	May 25, 2017 USD ($) $ / shares shares	Sep. 30, 2017 USD ($)
Initial Public Offering
Net proceeds		$ 334.7
Conversion ratio of stock-split	66,498.762
IPO
Initial Public Offering
Shares issued | shares	20,970,589
Share price (in dollars per share) | $ / shares	$ 17
Gross proceeds	$ 356.5
Issuance costs	21.8
Net proceeds	$ 334.7