Earnings (Loss) Per Share And Shareholder's Equity (Details) - USD ($)	6 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Oct. 22, 2015
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount				$ 2,000,000,000
Repurchases of ordinary shares, shares			0
Repurchases of ordinary shares	$ 500,000,000	$ 191,500,000
Common Stock
Equity, Class of Treasury Stock [Line Items]
Repurchases of ordinary shares, shares	3,300,000	2,700,000
Average repurchase price (in USD per share)	$ 151.59	$ 71.72
Repurchases of ordinary shares	$ 500,000,000	$ 191,500,000