Summary of Significant Accounting Policies (Details) $ / shares in Units, $ in Thousands										3 Months Ended		9 Months Ended
	Nov. 08, 2017 $ / shares	Sep. 15, 2017 $ / shares	Aug. 11, 2017 $ / shares	Jun. 16, 2017 $ / shares	May 12, 2017 $ / shares	Apr. 19, 2017 $ / shares	Mar. 22, 2017 $ / shares	Nov. 02, 2016 $ / shares shares	Oct. 14, 2016	Sep. 30, 2017 USD ($) $ / shares	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) $ / shares	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Dividend declarations
Cash dividends declared per common share | $ / shares			$ 0.12		$ 0.12		$ 0.12			$ 0.12		$ 0.36
Cash dividends paid per common share | $ / shares		$ 0.12		$ 0.12		$ 0.12
Cash and Restricted Cash
Restricted cash | $										$ 3,400		$ 3,400		$ 3,100
Accounts receivable
Allowance for doubtful accounts | $										9,300		9,300		12,300
Selling, general and administrative
Foreign currency translation and transactions
Transaction gain (loss) included in selling, general and administrative expense | $										$ 1,100	$ 800	$ 4,400	$ 4,700
Subsequent event
Dividend declarations
Cash dividends declared per common share | $ / shares	$ 0.12
VIE
Variable interest entities
Ownership percentage										40.00%		40.00%
Outstanding Balance | $										$ 0		$ 0		$ 0
Class of Stock, Common
Initial public offering
Shares converted | shares								11,556,495
Debt converted | shares								22,791,852
Stock split									9
Class of Stock, Common | Initial public offering
Initial public offering
Shares issued | shares								19,333,333
Share price (in dollars per share) | $ / shares								$ 17.00
Class of Stock, Common | Over-allotment option
Initial public offering
Shares issued | shares								2,899,999
Share price (in dollars per share) | $ / shares								$ 17.00
Magnus | Class of Stock, Common
Initial public offering
Shares purchased by Magnus | shares								14,818,720
Convertible debt
Initial public offering
Interest rate (as a percent)									7.50%