Planned Acquisition of Inotera and License Agreement with Nanya (Details) TWD / shares in Units, $ / shares in Units, TWD in Billions, $ in Billions		1 Months Ended	4 Months Ended	6 Months Ended
		Dec. 31, 2015	May. 01, 2016 TWD	Jun. 30, 2016 USD ($) $ / shares	Jun. 30, 2016 TWD	Jun. 30, 2016 TWD / shares	Dec. 14, 2015 TWD / $	Dec. 03, 2015	Sep. 03, 2015
Inotera [Member]
Acquisition of Remaining Inotera Shares [Abstract]
Current Equity Ownership Percentage (in hundredths)	[1]							33.00%	33.00%
Inotera [Member] | Nanya and certain of its affilliates [Member]
Acquisition of Remaining Inotera Shares [Abstract]
Percentage interest held by a third party (in hundredths)								32.00%
Subsequent Event [Member] | Inotera [Member] | Nanya and certain of its affilliates [Member]
Acquisition of Remaining Inotera Shares [Abstract]
Equity Method Investment Ownership Percentage Held By Third Party Subject to Voting and Support Agreements (in hundredths)		32.00%
Subsequent Event [Member] | Inotera [Member]
Acquisition of Remaining Inotera Shares [Abstract]
Foreign Currency Exchange Rate, Translation | TWD / $							32.7
Subsequent Event [Member] | Inotera [Member] | Scenario, Forecast [Member]
Acquisition of Remaining Inotera Shares [Abstract]
Ownership percentage after stock transactions (in hundredths)				100.00%	100.00%
Inotera Acquisition, Share Price | (per share)				$ 0.92		TWD 30
Acquisition of Remaining Inotera Shares, Potential Consideration [Abstract]
Aggregate consideration payable for Inotera shares not already owned | $				$ 4.1
Debt planned to be incurred toward consideration for Inotera shares not already owned				$ 2.5	TWD 80.0
Debt commitment letters planned to be obtained | TWD			TWD 80.0
Trading-day period used to derive average share value of equity interests issuable to Nanya				30 days	30 days
Number of days prior to the optional share issuance to Nanya that pricing is established				30 days	30 days
Subsequent Event [Member] | Inotera [Member] | Scenario, Forecast [Member] | Minimum [Member]
Acquisition of Remaining Inotera Shares [Abstract]
Business Combination Required Shareholder Affirmative Vote Percentage				66.66%	66.66%
Subsequent Event [Member] | Inotera [Member] | Scenario, Forecast [Member] | Maximum [Member] | Private Placement [Member]
Acquisition of Remaining Inotera Shares, Potential Consideration [Abstract]
Value of equity interests issuable to Nanya as consideration for Inotera shares not already owned				$ 1.0	TWD 31.5

[1] Entity is a variable interest entity.