CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Revenue:
Natural gas sales	$ 360,340	[1]	$ 452,726	[1]	$ 381,453	[1]
Natural gas liquids sales	814,916		723,063		490,980
Transportation, compression and processing fees	192,270	[1],[2]	121,631	[1],[2]	68,398	[1],[2]
Condensate and other	50,194	[1]	47,803	[1]	54,333	[1]
Total revenue	1,417,720		1,345,223		995,164
Costs and expenses:
Cost of natural gas and natural gas liquids	1,105,415	[1],[2],[3]	1,068,423	[1],[2],[3]	745,074	[1],[2],[3]
Transportation	25,199	[1],[2],[3]	24,225	[1],[2],[3]	22,701	[1],[2],[3]
Operations and maintenance	77,943		65,326		53,487
Depreciation and amortization	77,104		69,156		62,572
Impairment	29,486		8,409
General and administrative	50,648		48,680		40,347
Taxes other than income	7,392		5,130		4,726
Equity in loss from unconsolidated affiliates	137,088		145,324		20,480
Gain on sale of operating assets	(9,941)
Total costs and expenses	1,500,334		1,434,673		949,387
Operating (loss) income	(82,614)		(89,450)		45,777
Other income (expense):
Interest and other income	586		60		78
Loss on refinancing of unsecured debt			(18,233)
Interest and other financing costs	(55,264)		(47,187)		(53,605)
Loss before income taxes	(137,292)		(154,810)		(7,750)
Provision for income taxes	(1,678)		(1,502)		(931)
Net loss	(138,970)		(156,312)		(8,681)
Preferred unit distributions	(36,117)		(32,721)		(15,188)
Net loss to common units	$ (175,087)		$ (189,033)		$ (23,869)
Basic and diluted net loss per common unit (in dollars per unit)	$ (2.39)		$ (2.86)		$ (0.37)
Weighted average number of common units - basic and diluted	73,225		66,169		63,854
Distributions declared per common unit (in dollars per unit)	$ 2.30		$ 2.30		$ 2.30

[1] Inclusive of related party transactions discussed in Note 7.

[2] Inclusive of the following affiliate transactions discussed in Note 7: Transportation, compression and processing fees $17,874 $2,091 $11 Cost of natural gas and natural gas liquids $171,138 $19,290 $518 Transportation $9,514 $6,846 $5,478

[3] Exclusive of operations and maintenance and depreciation, amortization and impairment shown separately below.