Debt Obligations (Narrative) (Details) € in Millions, £ in Millions, CAD in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2015 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 CAD	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 29, 2012 USD ($)	Dec. 31, 2015 GBP (£)	Dec. 31, 2015 CAD	Sep. 30, 2015 EUR (€)	Sep. 18, 2015 CAD	Mar. 31, 2015 USD ($)	Mar. 31, 2015 EUR (€)	Jun. 30, 2014 CAD	May. 03, 2012 USD ($)	Oct. 06, 2010 CAD	Sep. 22, 2005 CAD
Debt Instrument [Line Items]
Leverage Ratio Following Acquisition			5.75x	5.75x
Other income (expense), net			$ 900,000		$ (6,500,000)	$ 18,900,000
Derivative, Cash Received on Hedge			16,000,000
Derivative, Notional Amount												$ 300,000,000
Line of Credit Facility, Maximum Borrowing Capacity | €										€ 100.0
Other short-term borrowings	$ 2,500,000		2,500,000		5,600,000
Amortization of Financing Costs		$ 1,300,000
Bank Overdrafts	18,700,000		18,700,000		64,600,000
Cash Held in Bank	39,600,000		39,600,000		80,000,000
Cash Held in Bank, Net of Bank Overdrafts	20,900,000		20,900,000		15,400,000
Short-term Debt	7,500,000		$ 7,500,000		4,900,000
Leverage Ratio In Fourth Year Following Acquisition			3.75x	3.75x
Convertible Senior Notes Due 2013 $575 Million 2.5% [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount						$ 575,000,000
Revolving Multicurrency Bank Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Term of Facility		5 years
Line of Credit Facility, Maximum Borrowing Capacity		$ 750,000,000
Debt Issuance Cost		1,800,000
Line of Credit Facility, Remaining Borrowing Capacity	750,000,000		$ 750,000,000
Line Of Credit YEN [Member]
Debt Instrument [Line Items]
Short-term Debt	$ 7,500,000		$ 7,500,000		$ 4,900,000
$300 million 2.0% notes due 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	0.95%		0.95%					0.95%	0.95%
$500 million 3.5% notes due 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	1.57%		1.57%					1.57%	1.57%
CAD 500 million 2.75% Notes Due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term			5 years	5 years
CAD 400 million 2.25% Notes Due 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term			3 years	3 years
CAD 900 million 5.0% notes due 2015 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount | CAD																	CAD 900.0
Derivative Instruments, Loss Recognized in Other Comprehensive Income (Loss), Effective Portion			$ 4,000,000
Series A notes due 2017 CAD 500 million 3.95% [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount | CAD																CAD 500.0
Derivative Instruments, Loss Recognized in Other Comprehensive Income (Loss), Effective Portion			$ 7,800,000
Overdraft facility (GBP) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			1.50%	1.50%
Line of Credit Facility, Maximum Borrowing Capacity | £								£ 20.0
Line of Credit Facility, Interest Rate Description			GBP LIBOR +1.5%	GBP LIBOR +1.5%
Line Of Credit GBP Overdraft Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity | £								10.0
Uncommitted money market facility (GBP) [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity | £								£ 10.0
Line Of Credit CAD [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity | CAD									CAD 30.0
Line of Credit Facility, Interest Rate Description			USD Prime or CAD Prime	USD Prime or CAD Prime
Overdraft Facility YEN 900M [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			0.45%	0.45%
Line of Credit Facility, Maximum Borrowing Capacity	$ 900,000,000		$ 900,000,000
Line of Credit Facility, Interest Rate Description			Japan base rate + 0.45%	Japan base rate + 0.45%
Overdraft Facility YEN 500M [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			0.35%	0.35%
Line of Credit Facility, Maximum Borrowing Capacity	500,000,000		$ 500,000,000
Line of Credit Facility, Interest Rate Description			Japan base rate + 0.35%	Japan base rate + 0.35%
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount															$ 1,900,000,000
Proceeds from issuances of long-term debt							$ 1,880,700,000
Underwriting Fees Related to Long-term Debt							14,700,000
Discounts to Long-term Debt							$ 4,600,000
Debt Issuance Costs, Capitalized															18,000,000
Senior Notes [Member] | $300 million 2.0% notes due 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	300,000,000		$ 300,000,000												$ 300,000,000
Derivative, Cash Received on Hedge			$ 700,000
Liabilities, Fair Value Adjustment	$ 700,000
Debt instrument, interest rate percentage	2.00%		2.00%					2.00%	2.00%						2.00%
Derivative, Notional Amount												$ 300,000,000	€ 265.0
Debt Instrument, Increase (Decrease) in Effective Cost of Borrowing			0.16%	0.16%
Senior Notes [Member] | $500 million 3.5% notes due 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 0		$ 0												$ 500,000,000
Derivative, Cash Received on Hedge			18,100,000
Liabilities, Fair Value Adjustment	$ 18,100,000		$ 7,300,000
Debt instrument, interest rate percentage	3.50%		3.50%					3.50%	3.50%						3.50%
Debt Instrument, Increase (Decrease) in Effective Cost of Borrowing			0.56%	0.56%
Senior Notes [Member] | CAD 500 million 2.75% Notes Due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount | CAD											CAD 500.0
Debt instrument, interest rate percentage	2.75%		2.75%					2.75%	2.75%		2.75%
Debt Instrument, Increase (Decrease) in Effective Cost of Borrowing			0.65%	0.65%
Senior Notes [Member] | CAD 400 million 2.25% Notes Due 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount | CAD											CAD 400.0
Debt instrument, interest rate percentage	2.25%		2.25%					2.25%	2.25%		2.25%
Debt Instrument, Increase (Decrease) in Effective Cost of Borrowing			0.16%	0.16%
Senior Notes [Member] | CAD 900 million 5.0% notes due 2015 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount | CAD									CAD 900.0								CAD 900.0
Debt instrument, interest rate percentage																	5.00%
Debt Instrument, Increase (Decrease) in Effective Cost of Borrowing			0.05%	0.05%
Senior Notes [Member] | Series A notes due 2017 CAD 500 million 3.95% [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 500,000,000		$ 500,000,000						CAD 500.0
Debt instrument, interest rate percentage	3.95%		3.95%					3.95%	3.95%
Debt Instrument, Increase (Decrease) in Effective Cost of Borrowing			0.23%	0.23%
Commercial Paper Program [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		750,000,000
Forward Starting Interest Rate Swap [Member]
Debt Instrument [Line Items]
Derivative, Notional Amount | CAD														CAD 600.0
Derivative Instruments, Loss Recognized in Other Comprehensive Income (Loss), Effective Portion			$ 29,500,000	CAD 39.2
Letter of Credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 100,000,000