Debt (Narrative) (Details)	12 Months Ended						1 Months Ended				0 Months Ended	12 Months Ended				0 Months Ended	12 Months Ended
	Dec. 31, 2011 USD ($)		Jan. 02, 2011 USD ($)		Jan. 03, 2010 USD ($)	Dec. 31, 2011 Commercial Paper [Member]	Jan. 31, 2009 7.25% Unsecured Notes due February 1, 2019 [Member] USD ($)	Dec. 31, 2011 7.25% Unsecured Notes due February 1, 2019 [Member] USD ($)	Jan. 02, 2011 7.25% Unsecured Notes due February 1, 2019 [Member] USD ($)	Jun. 17, 2011 Five-Year Revolving Credit Agreement Dated, August 8, 2006 [Member] USD ($)	Jun. 17, 2011 Four-Year Revolving Credit Agreement Dated, June 17, 2011 [Member] USD ($)	Dec. 31, 2011 Four-Year Revolving Credit Agreement Dated, June 17, 2011 [Member]	Sep. 07, 2011 AUS $50 million portion of Revolver [Member] AUD	Jun. 17, 2011 AUS $50 million portion of Revolver [Member] AUD	Jun. 17, 2011 USD $450 million portion of Revolver [Member] USD ($)	Sep. 07, 2011 Interest Rate Swap [Member] AUD	Dec. 31, 2011 Other Indebtedness [Member]
Debt Instrument [Line Items]
Commercial Paper Borrowings	$ 109,671,000		$ 0
Minimum interest rate																	0.00%
Maximum interest rate																	6.00%
Interest rate of debt instrument						0.50%	7.25%	7.25%	7.25%
Debt Instrument, Maturity year, start																	2012
Debt Instrument, Maturity year, end																	2016
Debt Instrument, Maturity date							Feb. 01, 2019				Jun. 17, 2015
Face amount of debt issued							400,000,000
Notes repurchase percentage of principal amount to be eligible for redemption							101.00%
Average borrowings outstanding	426,700,000		399,500,000
Weighted average interest rate of borrowings	7.00%		7.20%
Net interest expense incurred	29,100,000		27,900,000		29,000,000
Fair value of debt instrument	460,500,000	[1]	457,200,000	[1]				460,500,000	457,200,000
Termination of credit agreement										500,000,000
Current borrowing capacity														50,000,000	450,000,000
Maximum borrowing capacity											700,000,000
Minimum fee percentage for line of credit facility												0.08%
Maximum fee percentage for line of credit facility												0.20%
Line of credit facility minimum requirement of shareholder's equity											1,500,000,000
Carrying value of debt instrument	397,065,000		396,650,000					397,100,000	396,700,000
Borrowings outstanding	51,012,000		0							0			50,000,000
Debt Instrument, Interest Rate Terms												Any borrowings are made on an unsecured basis and bear interest at (a) for U.S. dollar borrowings, at the Company’s option, either (i) a fluctuating interest rate equal to the highest of JPMorgan’s prime rate, 0.50 percent above the Federal funds rate or the one-month eurodollar rate plus 1%, or (ii) the eurodollar rate for the applicable interest period, or (b) for Australian dollar borrowings, the bank bill rate, in each case plus an applicable margin that depends on the Company’s long-term debt ratings.
Types Of Interest Rate Derivatives Used																interest rate swap
Notional Amount of Cash Flow Hedge Instruments																50,000,000
Maximum Length of Time Hedged in Interest Rate Cash Flow Hedge																March 7, 2015
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate																4.5275%

[1] See Note 10 for carrying amount of these notes and borrowing.