Debt, Interest Rate Swap Arrangements (Details) - USD ($) $ in Millions	1 Months Ended
	Apr. 30, 2016	Apr. 02, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Proceeds from Hedge, Financing Activities	$ 61.0
Notional Amount Of Derivatives		$ 5,410.0	$ 6,630.0
Senior Notes [Member] | 1.30% Senior Notes Due 2017 [Member] | Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Notional Amount Of Derivatives		$ 900.0
Interest Rate Swap, Spread above One-month LIBOR		0.6616%
Interest Rate Swap, Variable Rate at Period End		1.0956%
Interest Rate Swap, Fixed Rate		1.30%
Senior Notes [Member] | 4.50% Senior Notes Due 2021 [Member] | Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Notional Amount Of Derivatives		$ 1,000.0
Interest Rate Swap, Spread above One-month LIBOR		3.442%
Interest Rate Swap, Variable Rate at Period End		3.8758%
Interest Rate Swap, Fixed Rate		4.50%
Senior Notes [Member] | 3.60% Senior Notes Due 2021 [Member] | Interest Rate Swaps [Member]
Debt Instrument [Line Items]
Notional Amount Of Derivatives		$ 1,100.0
Interest Rate Swap, Spread above One-month LIBOR		2.515%
Interest Rate Swap, Variable Rate at Period End		2.9165%
Interest Rate Swap, Fixed Rate		3.60%