Common Stock Repurchase Program (Details) - USD ($)	8 Months Ended	9 Months Ended		25 Months Ended
	Dec. 31, 2016	Dec. 31, 2016	Jan. 02, 2016	Dec. 31, 2016	May 16, 2016	Apr. 02, 2016	Nov. 17, 2014
Accelerated Share Repurchases [Line Items]
Treasury shares	0	0		0		0
Repurchase Program Two Thousand Fourteen [Member]
Accelerated Share Repurchases [Line Items]
Stock Repurchase Program, Authorized Amount							$ 800,000,000
Stock Repurchased During Period, Value				$ 800,000,000
Stock Repurchased and Retired During Period, Value		$ 414,000,000	$ 300,000,000
Stock Repurchased and Retired During Period, Shares		8,000,000	6,700,000
Repurchase Program Two Thousand Sixteen [Member] [Domain]
Accelerated Share Repurchases [Line Items]
Stock Repurchase Program, Authorized Amount					$ 1,000,000,000
Stock Repurchased During Period, Value	$ 209,800,000.0
Total amount available for future repurchases	$ 790,200,000	$ 790,200,000		$ 790,200,000