Partners' Capital, Equity and Incentive Compensation Plans (Summary of Award Activity Under 2010 Equity Incentive Plan and 2013 Equity Incentive Plan and Related Information) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
2013 Equity Incentive Plan | Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning balance, Options Outstanding (in shares)	1,369,270	1,058,297	867,882
Options, Granted (in shares)	674,081	468,875	229,693
Options, Exercised (in shares)	(6,188)	(155,902)	(29,543)
Options, Cancelled/Expired (in shares)		(2,000)	(9,735)
Ending balance, Options Outstanding (in shares)	2,037,163	1,369,270	1,058,297
Beginning balance, Weighted average exercise price options outstanding	$ 38.18	$ 31.72	$ 27.80
Weighted average exercise price options outstanding, Granted	34.05	50.66	45.78
Weighted average exercise price options outstanding, Exercised	21.50	31.89	25.70
Weighted average exercise price options outstanding, Cancelled/Expired		37.69	32.14
Ending balance, Weighted average exercise price options outstanding	36.86	38.18	31.72
Beginning balance, weighted average fair value, options	7.80	6.51	5.56
Weighted average fair value, granted, options	5.63	10.32	9.91
Weighted average fair value, vested, options	3.68	6.60	4.96
Weighted average fair value, cancelled/expired, options		8.77	6.95
Ending balance, weighted average fair value, options	$ 7.10	$ 7.80	$ 6.51
2013 Equity Incentive Plan | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning balance, Number of units (in shares)	381,864	414,691	394,908
Number of units, Granted (in shares)	348,152	228,576	237,563
Number of units, Exercised	(224,660)	(163,048)	(122,136)
Number of units, Cancelled/Expired (in shares)	(85,047)	(98,355)	(95,644)
Ending balance, Number of units (in shares)	420,309	381,864	414,691
Beginning balance, Weighted average exercise price units	$ 46.37	$ 40.67	$ 33.82
Weighted average exercise price units, Granted	35.27	49.86	45.53
Weighted average exercise price units, Exercised	46.23	40.63	33.26
Weighted average exercise price units, Cancelled/Expired	43.50	39.97	33.92
Ending balance, Weighted average exercise price units	$ 37.83	$ 46.37	$ 40.67
Class O Units | 2010 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning balance, Number of units (in shares)	568,040	1,134,811	1,292,899
Number of units, Exercised	(465,761)	(566,771)	(158,088)
Ending balance, Number of units (in shares)	102,279	568,040	1,134,811
Beginning balance, Weighted average exercise price units	$ 23.52	$ 24.06	$ 23.76
Weighted average exercise price units, Exercised	23.40	24.60	21.56
Ending balance, Weighted average exercise price units	24.05	23.52	24.06
Beginning balance, Weighted average fair value	5.00	3.62	3.68
Weighted average fair value, Exercised	4.76	2.24	4.18
Ending balance, Weighted average fair value	$ 5.67	$ 5.00	$ 3.62
Class RS Units | 2010 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning balance, Number of units (in shares)			39,875
Number of units, Released from restriction (in shares)			(39,875)
Beginning balance, Weighted average exercise price units			$ 22.18
Weighted average exercise price units, Released from restriction			$ 22.18