Components of Debt, Obligations, Weighted Average Interest Rate and Additional Fair Value Information Relating to Outstanding Debt Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Notes payable, carrying amount	$ 12,025	$ 9,738
Total notes payable and short-term borrowing	20,086	9,738
Long-term debt, carrying amount	27,930	34,475
Current portion of long-term debt, carrying amount	(10,465)	(10,325)
Total long-term debt, net of current portion, carrying amount	17,465	24,150
Short-term Debt
Debt Instrument [Line Items]
Short-term borrowing	8,061
Weighted Average Interest Rate	7.00%
Bank Borrowings
Debt Instrument [Line Items]
Long-term debt, carrying amount	21,000	24,500
Weighted Average Interest Rate	3.15%	2.92%
NeoPhotonics Semiconductor
Debt Instrument [Line Items]
Long-term debt, carrying amount	$ 6,930	$ 9,975
Weighted Average Interest Rate	1.50%	1.50%