Equity-Based Compensation Plans And Employee Benefit Plans (Summary Of Service-Based And Performance-Based Awards) (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares shares
Service-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Unvested at December 31, 2013, Number of Phantom Units | shares	112,823
Unvested at December 31, 2013, Average Grant Date Fair Value | $ / shares	$ 44.53
Unvested at December 31, 2013, Total Value | $	$ 5,024
Granted, Number of Phantom Units | shares	58,192
Granted, Average Grant Date Fair Value | $ / shares	$ 44.40
Granted, Total Value | $	$ 2,584
Forfeited, Number of Phantom Units | shares	(2,856)
Forfeited, Average Grant Date Fair Value | $ / shares	$ 47.26
Forfeited, Total Value | $	$ (135)
Settled, Number of Phantom Units | shares	(35,483)
Settled, Average Grant Date Fair Value | $ / shares	$ 30.79
Settled, Total Value | $	$ (1,093)
Unvested at December 31, 2014, Number of Phantom Units | shares	132,676.000
Unvested at December 31, 2014, Average Grant Date Fair Value | $ / shares	$ 48.09
Unvested at December 31, 2014, Total Value | $	$ 6,380
Performance-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Unvested at December 31, 2013, Number of Phantom Units | shares	313,845
Unvested at December 31, 2013, Average Grant Date Fair Value | $ / shares	$ 42.82
Unvested at December 31, 2013, Total Value | $	$ 13,439
Granted, Number of Phantom Units | shares	154,633
Granted, Average Grant Date Fair Value | $ / shares	$ 45.15
Granted, Total Value | $	$ 6,982
Forfeited, Number of Phantom Units | shares	(4,201)
Forfeited, Average Grant Date Fair Value | $ / shares	$ 46.00
Forfeited, Total Value | $	$ (193)
Settled, Number of Phantom Units | shares	(120,069)
Settled, Average Grant Date Fair Value | $ / shares	$ (31.50)
Settled, Total Value | $	$ 3,782
Unvested at December 31, 2014, Number of Phantom Units | shares	344,208.000
Unvested at December 31, 2014, Average Grant Date Fair Value | $ / shares	$ 47.78
Unvested at December 31, 2014, Total Value | $	$ 16,446