Long-term Debt Credit Agreement (Details)	12 Months Ended												12 Months Ended		3 Months Ended			12 Months Ended			3 Months Ended						12 Months Ended			3 Months Ended						12 Months Ended															1 Months Ended	12 Months Ended			12 Months Ended
	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Jul. 29, 2011 USD ($)	Oct. 15, 2010 USD ($)	Dec. 31, 2012 Base Rate [Member]	Dec. 31, 2012 Libor Interest Rate [Member]	Jan. 02, 2013 Minimum [Member]	Jan. 02, 2013 Minimum [Member] Base Rate [Member]	Jan. 02, 2013 Minimum [Member] Libor Interest Rate [Member]	Jan. 02, 2013 Maximum [Member]	Jan. 02, 2013 Maximum [Member] Base Rate [Member]	Jan. 02, 2013 Maximum [Member] Libor Interest Rate [Member]	Dec. 31, 2012 Series B Senior Notes [Member] USD ($)	Dec. 31, 2011 Series B Senior Notes [Member]	Dec. 31, 2012 United States Term Loan [Member] USD ($)	Oct. 02, 2012 United States Term Loan [Member] USD ($)	Jul. 29, 2011 United States Term Loan [Member] USD ($)	Dec. 31, 2012 United States Term Loan [Member] 12/31/2012 - 9/30/2014 [Member] USD ($)	Dec. 31, 2012 United States Term Loan [Member] 12/31/2014 - 9/30/2016 [Member] USD ($)	Dec. 31, 2012 United States Term Loan [Member] 12/31/2016 - 9/30/2017 [Member] USD ($)	Dec. 31, 2012 Canadian Term Loan [Member] CAD	Nov. 01, 2012 Canadian Term Loan [Member] USD ($)	Oct. 02, 2012 Canadian Term Loan [Member] USD ($)	Oct. 02, 2012 Canadian Term Loan [Member] CAD	Jul. 29, 2011 Canadian Term Loan [Member] USD ($)	Jul. 29, 2011 Canadian Term Loan [Member] CAD	Dec. 31, 2012 Canadian Term Loan [Member] 12/31/2012 - 9/30/2014 [Member] CAD	Dec. 31, 2012 Canadian Term Loan [Member] 12/31/2014 - 9/30/2016 [Member] CAD	Dec. 31, 2012 Canadian Term Loan [Member] 12/31/2016 - 9/30/2017 [Member] CAD	Dec. 31, 2012 Australian Term Loan [Member] AUD	Oct. 25, 2012 Australian Term Loan [Member] USD ($)	Oct. 02, 2012 Australian Term Loan [Member] USD ($)	Oct. 02, 2012 Australian Term Loan [Member] AUD	Jul. 29, 2011 Australian Term Loan [Member] USD ($)	Jul. 29, 2011 Australian Term Loan [Member] AUD	Dec. 31, 2012 Australian Term Loan [Member] 12/31/2012 - 9/30/2014 [Member] AUD	Dec. 31, 2012 Australian Term Loan [Member] 12/31/2014 - 9/30/2016 [Member] AUD	Dec. 31, 2012 Australian Term Loan [Member] 12/31/2016 - 9/30/2017 [Member] AUD	Oct. 02, 2012 Revolving Credit Facility [Member] USD ($)	Dec. 31, 2012 United States Revolver [Member] USD ($)	Dec. 31, 2012 Australia Revolving Loan [Member] USD ($)	Dec. 31, 2012 European revolver [Member] [Member] USD ($)	Dec. 31, 2012 European revolver [Member] [Member] EUR (€)	Dec. 31, 2012 Letter of Credit [Member] USD ($)	Dec. 31, 2012 Swingline U.S. [Member] USD ($)	Dec. 31, 2012 Swingline Canada [Member] USD ($)	Dec. 31, 2012 Swingline Australia [Member] USD ($)	Dec. 31, 2012 Swingline Europe [Member] USD ($)	Dec. 31, 2012 Previous Revolving Loan [Member] USD ($)	Oct. 28, 2011 Previous Revolving Loan [Member] USD ($)	Oct. 31, 2012 Total Credit Facility [Member]	Dec. 31, 2012 Total Credit Facility [Member] USD ($)	Oct. 02, 2012 Total Credit Facility [Member] USD ($)	Sep. 30, 2012 Total Credit Facility [Member] USD ($)	Dec. 31, 2012 Prior Credit Agreement [Member] USD ($)
Debt Instrument [Line Items]
Make-whole payment													$ 12,600,000
Write off of deferred financing fees	3,200,000	500,000																																																					2,900,000
Line of Credit Facility, Maximum Borrowing Capacity			750,000,000	620,000,000												1,600,000,000	200,000,000								25,000,000	23,600,000								100,000,000	92,200,000				425,000,000					45,000,000	30,000,000	15,000,000	15,000,000	10,000,000		425,000,000			2,300,000,000	750,000,000
Debt instrument, maturity date	Jul. 29, 2016												Jul. 26, 2015																																						Oct. 01, 2017
Line of Credit Facility, Amount Outstanding																							25,000,000	24,600,000								210,000,000	202,900,000							11,000,000	10,400,000	3,800,000	2,900,000						25,200,000
Debt Instrument, Basis Spread on Variable Rate					1.50%	2.50%		0.50%	1.50%		1.75%	2.75%
Debt Instrument, Interest Rate, Stated Percentage													5.36%	5.36%	2.71%						3.55%									5.65%										2.71%		2.56%	2.56%
Line Of Credit, Unused Borrowing Capacity, Commitment Fee Rate	0.50%						0.25%			0.50%
Debt Instrument, Periodic Payment, Principal																		16,400,000	21,900,000	43,700,000							200,000	300,000	700,000							2,000,000	2,700,000	5,400,000
Repayments of term loan in local currency															47,500,000						10,000,000									18,000,000
Repayment of term loan in USD																						10,000,000									18,600,000
Debt Instrument, Unused Borrowing Capacity, Amount																																																	396,300,000
Letters of Credit Outstanding, Amount																																																	3,600,000
Legal Fees																																																				$ 500,000