Debt (Summary Of Debt Instruments) (Details)	0 Months Ended	3 Months Ended				3 Months Ended		3 Months Ended
	Mar. 13, 2012	Mar. 31, 2012 USD ($)		Dec. 31, 2011 USD ($)		Mar. 31, 2012 Term Note Payable-Domestic, June 22, 2011 [Member] USD ($)	Jun. 22, 2011 Term Note Payable-Domestic, June 22, 2011 [Member] USD ($)	Mar. 31, 2012 Commercial Paper [Member]	Mar. 31, 2012 Line Of Credit [Member] Term Note Payable-Domestic, June 22, 2011 [Member] USD ($)	Mar. 31, 2012 Swing Line Loans [Member] Term Note Payable-Domestic, June 22, 2011 [Member] USD ($)	Mar. 31, 2012 Swing Line Loans [Member] Amended And Restated [Member] USD ($)	Mar. 31, 2012 GBP [Member] GBP (£)	Mar. 31, 2012 Maximum [Member] Term Note Payable-Domestic, June 22, 2011 [Member]	Mar. 31, 2012 Maximum [Member] Eurodollar Rate [Member]	Mar. 31, 2012 Minimum [Member] Term Note Payable-Domestic, June 22, 2011 [Member]	Mar. 31, 2012 Minimum [Member] Eurodollar Rate [Member]
Debt Instrument [Line Items]
Term note payable		$ 288,750,000	[1]	$ 292,500,000	[1]		$ 300,000,000
Revolving line of credit		100,000,000	[1]	125,000,000	[1]		600,000,000		20,000,000	20,000,000	110,000,000
Swing line of credit		63,960,000	[1]
Other debt		1,532,000		1,283,000
Total notes payable and other obligations		454,242,000		418,783,000
Securitization Facility		341,000,000	[2]	280,000,000	[2]
Current portion		520,359,000		420,354,000
Long-term portion		274,883,000		278,429,000
Total notes payable, credit agreements and Securitization Facility		795,242,000		698,783,000
United Kingdom entities as designated borrowers	two
Borrowings outstanding on the term loan and revolving line of credit						289,000,000
Borrowings outstanding on the revolving line of credit		100,000,000
Borrowing outstanding on the foreign currency swing line		64,000,000										40,000,000
Interest on the line of credit, sum of rate plus													1.25%	2.25%	0.25%	1.25%
Principal payment due						Jun. 01, 2016
Principal payments on term loan						3,800,000
Current purchase limit under the securitization facility		500,000,000
Securitization facility termination date		February 4, 2013
Program fee rate								0.26%
Program fee variable rate								0.75%
Unused facility fee payable rate		0.35%
Deferred debt issuance costs		$ 6,300,000

[1] The Company entered into a $300 million term loan and a $600 million revolving line of credit on June 22, 2011. The revolving line of credit contains a $20 million sublimit for letters of credit, a $20 million sublimit for swing line loans and a sublimit for multicurrency borrowings in Euros, Sterling and Japanese Yen. Proceeds from this new credit facility were used to retire the Company's indebtedness under its 2005 Credit Facility and CCS Credit Facility, as described below. On March 13, 2012, the Company entered into the first amendment to the Credit Agreement. This Amendment added two United Kingdom entities as designated borrowers and added a $110 million foreign currency swing line sub facility under the existing revolver, which will allow for alternate currency borrowing on the swing line. At March 31, 2012, the Company had $289 million borrowings outstanding on the term loan, $100 million outstanding on the revolving line of credit and $64 million (£40 million GBP) outstanding on the foreign currency swing line, respectively. Interest on the line of credit ranges from the sum of the Base Rate plus 0.25% to 1.25% or the Eurodollar Rate plus 1.25% to 2.25%. The term note is payable in quarterly installments and is due on the last business day of each March, June, September, and December with the final principal payment due in June 2016. Borrowings on the revolving line of credit are repayable at our option of one, two, three or six months after borrowing, depending on the term of the borrowing on the facility. Borrowings on the foreign swing line of credit are due no later than ten business days after such loan is made. This facility is referred to as the Credit Facility. Principal payments of $3.8 million were made on the term loan during the three months ended March 31, 2012.

[2] The Company is party to a receivables purchase agreement (Securitization Facility) that was amended and restated for the fourth time as of October 29, 2007 and which has been amended seven times since then to add or remove purchasers, extend the facility termination date and remove all financial covenants. The current purchase limit under the Securitization Facility is $500 million. The Securitization Facility was amended for the seventh time on February 6, 2012 to add a new purchaser and extend the facility termination date to February 4, 2013. There is a program fee equal to the Commercial Paper Rate of 0.26%, plus 0.75% as of March 31, 2012. The unused facility fee is payable at a rate of 0.35% per annum as of March 31, 2012. The Securitization Facility provides for certain termination events, which includes nonpayment, upon the occurrence of which the administrator may declare the facility termination date to have occurred, may exercise certain enforcement rights with respect to the receivables, and may appoint a successor servicer, among other things.