Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Contingency [Line Items]
Statutory income tax rate		35.00%
Partial unpaid interest amount waiver on intercompany loan			$ 174,000
Income tax benefit recognized	$ 17,800
Permanent impairment			(62,334)
Net deferred tax assets	171	$ 183	171	$ 577
Deferred tax assets, valuation allowance amount	279,867	281,473	279,867	194,739	$ 178,729
Net operating loss carry-forwards		684,851
Net operating loss utilized		$ 279	121	1,219
Net operating loss expiration date		2036
Unrecognized tax benefits	2,139	$ 2,459	2,139	3,491
Income tax benefits by reversing liabilities		670	1,606	110
Income tax expenses for uncertain tax positions		687	351	44
Recognized interest and penalties as income tax expense		334	45	10
Total interest and penalties accrued	$ 359	$ 691	$ 359	$ 480
Korean Subsidiary [Member]
Income Tax Contingency [Line Items]
Statutory income tax rate		24.20%	24.20%	24.20%
Net operating loss carry-forwards		$ 280,417
Net operating loss expiration date		2026
Luxembourg Subsidiary [Member]
Income Tax Contingency [Line Items]
Net operating loss carry-forwards		$ 268,959
Korean Statutory Tax Rate [Member]
Income Tax Contingency [Line Items]
Tax credit carry-forwards		$ 6,738
Net operating loss carry-forwards, expiration period		The Korean tax credits expire at various dates starting from 2017 to 2021
Dutch [Member]
Income Tax Contingency [Line Items]
Tax credit carry-forwards		$ 13,121
Net operating loss carry-forwards, expiration period		Indefinite period of time
U.S [Member]
Income Tax Contingency [Line Items]
Tax credit carry-forwards		$ 390