Long-Term Debt (Schedule Of Revolving Credit Facility) (Details) - USD ($)		6 Months Ended	12 Months Ended
	Sep. 06, 2013	Jul. 03, 2015	Dec. 31, 2014	Dec. 31, 2013	Jul. 22, 2011
Debt Instrument [Line Items]
Outstanding borrowings		$ 1,187,400,000	$ 1,325,500,000
Outstanding letters of credit		55,400,000
Equity interest pledged in all domestic subsidiaries, percentage	100.00%
Non-voting equity interest pledged in certain foreign subsidiaries, percentage	100.00%
Europe [Member]
Debt Instrument [Line Items]
Outstanding borrowings		9,100,000	10,500,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	$ 1,000,000,000.0				$ 400,000,000
Capital expenditures to fixed charges ratio	100.00%
Increase, additional borrowings	$ 250,000,000
Capitalized deferred finance costs		900,000	1,700,000	$ 4,900,000
Threshold for line of credit facility percentage of asset based revolving credit facilities	10.00%
Outstanding borrowings		180,100,000	136,800,000
Total credit under facility		1,000,000,000	1,000,000,000
Undrawn availability		$ 375,300,000	$ 425,000,000
Interest rate		2.50%	2.10%
Outstanding letters of credit		$ 41,200,000	$ 58,500,000
Original issuance		Jul. 31, 2011	Jul. 31, 2011
Maturity date		Sep. 30, 2018	Sep. 30, 2018
Equity interest pledged	65.00%
Revolving Credit Facility [Member] | UNITED STATES [Member]
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity					630,000,000
Undrawn availability		$ 230,500,000	$ 257,700,000
Revolving Credit Facility [Member] | CANADA [Member]
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity					70,000,000
Undrawn availability		50,500,000	54,300,000
Revolving Credit Facility [Member] | Europe [Member]
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity					$ 300,000,000
Undrawn availability		$ 94,300,000	$ 113,000,000
Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Threshold for line of credit facility borrowings	$ 100,000,000
Line of Credit Facility, Commitment Fee Percentage	0.25%
Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.375%