Bank Credit Agreements and Other Short-Term and Long-Term Debt - Schedule of Debt (Parenthetical) (Details) - Notes Payable To Bank - TWD TWD in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term Debt, Gross	TWD 132
Long-term variable interest rate		1.90%
Debt Instrument, Maturity Date, Description	TWD 132 million, variable interest (approximately 1.9% as of December 31, 2015), matures July 6, 2021
Debt instrument, maturity date	Jul. 06, 2021