Income taxes - Schedule of Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Effective income tax rate reconciliation
Federal statutory rate (as a percent)	21.00%
State franchise taxes (as a percent)	1.00%	(0.40%)	(0.10%)
Non-Controlling Interest (as a percent)	(14.10%)
Other Miscellaneous Permanent Differences (as a percent)	(0.30%)
Undistributed earnings of foreign subsidiaries (as a percent)	(2.60%)	(17.90%)	2.40%
U.S. Federal tax related to foreign effectively connected income (as a percent)	(0.20%)	(3.10%)
Effective tax rate (as a percent)	(11.80%)	(105.20%)	23.10%
Canada
Effective income tax rate reconciliation
Income tax provision (as a percent)	(0.40%)	(0.60%)	0.40%
Mexico
Effective income tax rate reconciliation
Income tax provision (as a percent)	(6.30%)	(29.60%)	9.10%
Poland
Effective income tax rate reconciliation
Income tax provision (as a percent)	(5.90%)	(29.20%)	6.70%
Czech Republic
Effective income tax rate reconciliation
Income tax provision (as a percent)		(1.10%)	(0.10%)
Ireland and United Kingdom
Effective income tax rate reconciliation
Income tax provision (as a percent)	(0.10%)	(0.10%)
Germany
Effective income tax rate reconciliation
Income tax provision (as a percent)			(1.80%)
Spain
Effective income tax rate reconciliation
Income tax provision (as a percent)	(3.90%)	(23.20%)	6.50%