Shareholders' Equity - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2016 EUR (€) € / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2015 € / shares	Aug. 31, 2015 shares	Jan. 14, 2015 shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2014 € / shares
Class Of Stock [Line Items]
Ordinary shares, value authorized	$ 400,000	€ 40,000
Ordinary shares, shares authorized	350,000,000	350,000,000	350,000,000
Ordinary shares, par value | $ / shares	$ 0.001		$ 0.001
Deferred Ordinary shares | $	$ 54,000		$ 54,000				$ 54,000
Deferred ordinary shares, par value | (per share)	$ 1.35	€ 1.00	$ 1.35	€ 1.00			$ 1.35	€ 1.00
Deferred ordinary shares, shares authorized	39,994	39,994	39,994				40,000
Deferred ordinary shares, shares issued	39,994	39,994	39,994			40,000
Cash payment for ordinary shareholders upon winding up | $	$ 5,000,000
Preferred shares, shares authorized	50,000,000	50,000,000	50,000,000
Preferred shares, par value | $ / shares	$ 0.001		$ 0.001
Preferred shares, shares issued	0	0	0
Richard Ressler
Class Of Stock [Line Items]
Deferred Ordinary Shares Transferred					39,994