Condensed Consolidated Balance Sheets (Parenthetical) $ in Millions	Jun. 30, 2018 USD ($) $ / shares shares	Jun. 30, 2018 € / shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2017 € / shares
Statement of Financial Position [Abstract]
Allowance for doubtful accounts | $	$ 6.5		$ 6.2
Stockholders' Equity:
Preferred shares, par value (in USD per share) | $ / shares	$ 0.0001		$ 0.0001
Preferred shares, authorized	10,000,000		10,000,000
Ordinary shares, par value (in EUR per share) | € / shares		€ 0.001		€ 0.001
Ordinary shares, authorized	10,000,000,000		10,000,000,000