Debt And Financing Transactions (Narrative) (Details) (USD $)	3 Months Ended	12 Months Ended	3 Months Ended	0 Months Ended	3 Months Ended					3 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2012 Senior Secured Credit Facility [Member]	Dec. 21, 2010 Senior Second Priority Secured Notes [Member]	Mar. 31, 2012 Senior Second Priority Secured Notes [Member]	Mar. 31, 2012 Fixed Rate Notes [Member]	Dec. 31, 2011 Fixed Rate Notes [Member]	Mar. 31, 2012 Workers Compensation And Self Insurance Liability [Member] Senior Secured Credit Facility [Member]	Dec. 21, 2010 Private Placement [Member] Senior Second Priority Secured Notes [Member]	Mar. 31, 2012 First Lien Term Loan B-1 [Member] Senior Secured Credit Facility [Member]	Mar. 31, 2012 First Lien Term Loan B-2 [Member] Senior Secured Credit Facility [Member]	Mar. 31, 2012 June 30, 2012 To December 2013 [Member]	Mar. 31, 2012 December 2013 To December 2016 [Member]	Mar. 31, 2012 Due December 2016 [Member] Senior Secured Credit Facility [Member]	Mar. 31, 2012 Due December 2015 [Member] Senior Secured Credit Facility [Member]	Mar. 31, 2012 Maturity In December 2017 [Member]
Debt Instrument [Line Items]
Deferred loan costs	$ 12,800,000	$ 22,300,000
Original aggregate principal amount of credit facility														1,070,000,000
Face value first lien term loan			874,000,000							200,000,000	674,000,000
LIBOR rate plus			LIBOR rate plus 4.50%							LIBOR rate plus 3.75%	LIBOR rate plus 3.75%
Minimum LIBOR rate			LIBOR rate of 1.50%								LIBOR rate of 1.25%
Basis spread on variable rate			4.50%							3.75%	3.75%
Net of unamortized original issue discount										500,000	1,700,000
Debt instrument principal payment											1,685,000	5,000,000	10,000,000
Maturity date of note			December 21, 2015		November 2018	May 15, 2017								December 2016	December 2015	December 2017
Increase in term loans or revolving commitment	250,000,000
Revolving line of credit								162,200,000							400,000,000
Original issue discount on debt				10,000,000
Proceeds from issuance of senior notes				490,000,000
Available balance under revolving line of credit															237,800,000
Revolving line of credit capacity			400,000,000
Outstanding letters of credit fees incurred			4.50%
Rate at which interest accrues				10.00%
Face value of second priority senior notes									500,000,000
Fixed interest rates on notes						12.50%
Debt instrument principal payments, percentage											0.25%
Total long-term debt	1,384,477,000	1,440,746,000				15,238,000	15,638,000
Loss on debt extinguishment	$ 20,940,000