Fair Value Measurements (Details) In Millions, except Share data, unless otherwise specified	0 Months Ended
	Sep. 07, 2011	Dec. 31, 2011	Sep. 07, 2011 Eris [Member] USD ($)	Sep. 07, 2011 Eris [Member] TWD
Fair Value Option Quantitative Disclosures [Line Items]
Number Of Common Stock Shares Purchased		12,413,604
Price Paid Per Common Stock Share				39
Amount Paid For Common Stock Shares			$ 14	390
Percentage Of Ownership			30.00%	30.00%
Sale of Stock, Number of Shares Issued in Transaction	10,000,000