Equity-Based Compensation Plans And Employee Benefit Plans (Narrative) (Details) (USD $)	3 Months Ended	12 Months Ended					3 Months Ended	12 Months Ended						3 Months Ended	12 Months Ended					12 Months Ended								12 Months Ended
	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011 2010 Long Term Incentive Plan [Member] years	Dec. 31, 2010 2010 Long Term Incentive Plan [Member]	Mar. 31, 2010 2007 Long Term Incentive Plan [Member]	Dec. 31, 2010 2007 Long Term Incentive Plan [Member]	Dec. 31, 2009 2007 Long Term Incentive Plan [Member]	Dec. 31, 2011 Stock Appreciation Rights Plan [Member] years	Dec. 31, 2010 Stock Appreciation Rights Plan [Member]	Dec. 31, 2009 Stock Appreciation Rights Plan [Member]	Dec. 31, 2010 Series B Units [Member]	Mar. 31, 2010 Class B Membership Interests [Member]	Dec. 31, 2010 Class B Membership Interests [Member]	Dec. 31, 2009 Class B Membership Interests [Member]	Dec. 31, 2010 Bonus Program [Member]	Dec. 31, 2009 Bonus Program [Member]	Dec. 31, 2011 Bonus Program [Member]	Dec. 31, 2011 Profit-Sharing And Retirement Savings Plan [Member]	Dec. 31, 2010 Profit-Sharing And Retirement Savings Plan [Member]	Dec. 31, 2009 Profit-Sharing And Retirement Savings Plan [Member]	Dec. 31, 2011 Health Care Benefit Programs [Member]	Dec. 31, 2010 Health Care Benefit Programs [Member]	Dec. 31, 2009 Health Care Benefit Programs [Member]	Dec. 31, 2011 Class A Units [Member]	Dec. 31, 2011 Waiver Units [Member]	Dec. 31, 2011 Maximum [Member]	Dec. 31, 2011 Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Phantom units awarded during the period					151,916	62,927
Performance Based Award Percentage																												150.00%	50.00%
Weighted average grant date fair value of phantom unit						$ 20.64
Compensation expense					$ 1,900,000	$ 400,000	$ 500,000		$ 1,000,000	$ 600,000	$ 5,200,000	$ 3,400,000
Non-cash compensation charge	75,600,000		76,923,000	14,104,000												14,100,000
Unrecognized compensation cost					4,000,000					200,000
Weighted average period of recognition, years					2					1
Liability for compensation awards					2,000,000	300,000
Phantom units vested								123,857
Number of common units per right			1
Term of awards, years										10
Total intrinsic value of rights exercised										2,400,000	1,300,000	100,000
Units received from general partner													767
Number of common units issued	64,615,000	71,965,000	64,615,000																							2,364,279	827,484
Non-cash compensation expense		(15,000)	4,706,000	4,248,000									79,100,000
Deferred compensation expenses															14,900,000	15,400,000
Decrease in compensation expenses														2,100,000
Weighted percentage of target level of available cash before reserves																	90.00%
Weighted percentage of achievement level of available cash before reserves																	10.00%
Accrued bonus																			6,100,000
Bonus paid																	5,200,000	3,900,000
Employer contribution percentage to retirement plan		6.00%
Employer profit-sharing contribution percentage		3.00%
Employee retirement plan expenses																				2,600,000	2,700,000	2,200,000
Health care benefits																							$ 8,100,000	$ 6,500,000	$ 6,200,000