Short-term and Long-term Obligations - Short-term Obligations (Details)	1 Months Ended		6 Months Ended
	Nov. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 TWD	Nov. 30, 2015 TWD
Short-term Debt [Line Items]
Debt, outstanding balance		$ 94,412,000	$ 94,233,000
Line of Credit | Revolving Credit Facility
Short-term Debt [Line Items]
Debt, outstanding balance		$ 69,399,000	$ 71,899,000
Bank of America | Minimum
Short-term Debt [Line Items]
Interest rate (as a percent)		0.79%	0.89%	0.89%
Bank of America | Maximum
Short-term Debt [Line Items]
Interest rate (as a percent)		1.68%	1.74%	1.74%
Bank of America | Line of Credit | Revolving Credit Facility
Short-term Debt [Line Items]
Line of credit, total outstanding balance		$ 59,699,000	$ 62,199,000
Credit facility, remaining borrowing capacity			2,801,000
Credit facility, maximum borrowing capacity		65,000,000
Debt, outstanding balance		59,699,000	62,199,000
Amount of assets as collateral for credit facility		1,045,408,000	$ 1,148,460,000
Bank of America | Line of Credit | Revolving Credit Facility | LIBOR
Short-term Debt [Line Items]
LIBOR rate (as a percent)			0.24%	0.24%
Credit facility, basis spread on variable rate (as a percent)			1.25%
Bank of America | Term Loan
Short-term Debt [Line Items]
Debt, total outstanding borrowings		$ 3,733,000	$ 2,333,000
Credit facility, term		5 years
Amount of assets as collateral for credit facility		$ 17,354,000	17,239,000
Bank of America | Term Loan | LIBOR
Short-term Debt [Line Items]
Credit facility, basis spread on variable rate (as a percent)		1.50%
CTBC Bank | CTBC 2014 Facility
Short-term Debt [Line Items]
Credit facility, remaining borrowing capacity			$ 639,000	TWD 21,025,000
Credit facility, maximum borrowing capacity	$ 30,340,000				TWD 1,000,000,000
CTBC Bank | Minimum | CTBC 2014 Facility
Short-term Debt [Line Items]
Interest rate (as a percent)		0.82%	0.79%	0.79%
CTBC Bank | Maximum | CTBC 2014 Facility
Short-term Debt [Line Items]
Interest rate (as a percent)		1.16%	1.14%	1.14%
CTBC Bank | Line of Credit | Revolving Credit Facility | CTBC 2014 Facility
Short-term Debt [Line Items]
Credit facility, term	12 months
Credit facility, maximum borrowing capacity	$ 17,000,000
Percent of eligible accounts receivable	80.00%				80.00%
Debt, outstanding balance		$ 9,700,000	$ 9,700,000
CTBC Bank | Line of Credit | Revolving Credit Facility | CTBC's Established USD Interest Rate | CTBC 2014 Facility
Short-term Debt [Line Items]
Credit facility, basis spread on variable rate (as a percent)	0.30%
CTBC Bank | Term Loan | CTBC 2014 Facility
Short-term Debt [Line Items]
Line of credit, total outstanding balance		21,280,000	20,001,000
Debt, outstanding balance		21,280,000	20,001,000
Amount of assets as collateral for credit facility		$ 27,047,000	$ 26,939,000
CTBC Bank | Term Loan | Secured Debt | CTBC 2014 Facility
Short-term Debt [Line Items]
Credit facility, term	12 months
Credit facility, maximum borrowing capacity	$ 22,017,000				TWD 700,000,000
CTBC Bank | Term Loan | Secured Debt | CTBC's Established NTD Interest Rate | CTBC 2014 Facility
Short-term Debt [Line Items]
Credit facility, basis spread on variable rate (as a percent)	0.25%