Derivative Instrument (Notional Table) (Details) - USD ($)		3 Months Ended	6 Months Ended
		Dec. 31, 2014	Jun. 30, 2015
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | USD
Derivatives Fair Value [Line Items]
Derivative, Notional Amount		$ 57,000,000	$ 57,000,000
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | CAD
Derivatives Fair Value [Line Items]
Derivative, Notional Amount		58,000,000	61,000,000
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | GBP
Derivatives Fair Value [Line Items]
Derivative, Notional Amount		40,000,000	60,000,000
Designated as Hedging Instrument [Member] | Net Investment Hedging [Member] | CAD
Derivatives Fair Value [Line Items]
Derivative, Notional Amount		900,000,000	1,175,000,000
Notional Amount Of Nonderivative Instruments		250,000,000	250,000,000
Designated as Hedging Instrument [Member] | Net Investment Hedging [Member] | GBP
Derivatives Fair Value [Line Items]
Derivative, Notional Amount		350,000,000	550,000,000
Notional Amount Of Nonderivative Instruments		1,050,000,000	1,050,000,000
Not Designated as Hedging Instrument [Member] | CAD
Derivatives Fair Value [Line Items]
Derivative, Notional Amount	[1]	$ 12,000,000	$ 700,000,000

[1] (1) These non-designated instruments represent off-setting forward exchange contracts to manage against adverse movements in exchange rates with regards to the purchase price on pending foreign acquisitions.