Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current Assets:
Cash and cash equivalents	$ 53	$ 1
Trade accounts receivable, net of allowance of $1 and $1	40	44
Accrued revenues	107	68
Related party receivables	4	45
Derivative assets	4	4
Other current assets	29	25
Total current assets	237	187
Property, Plant and Equipment:
Gathering and transmission systems	852	699
Compression equipment	961	847
Gas plants and buildings	232	195
Other property, plant and equipment	189	148
Construction-in-progress	283	192
Total property, plant and equipment	2,517	2,081
Less accumulated depreciation	(355)	(195)
Property, plant and equipment, net	2,162	1,886
Other Assets:
Investment in unconsolidated affiliates	2,214	1,925
Long-term derivative assets	1	0
Other, net of accumulated amortization of debt issuance costs of $17 and $10	41	39
Total other assets	2,256	1,964
Intangible Assets and Goodwill:
Intangible assets, net of accumulated amortization of $74 and $45	712	741
Goodwill	790	790
Total intangible assets and goodwill	1,502	1,531
TOTAL ASSETS	6,157	5,568
Current Liabilities:
Drafts payable	6	3
Trade accounts payable	102	73
Accrued cost of gas and liquids	83	85
Related party payables	37	13
Deferred revenues	17	16
Derivative liabilities	1	11
Other current liabilities	41	33
Total current liabilities	287	234
Long-term derivative liabilities	25	39
Other long-term liabilities	5	6
Long-term debt, net	2,157	1,687
Commitments and contingencies
Series A Preferred Units, redemption amount of $85 and $85	73	71
Partners’ Capital and Noncontrolling Interest:
Common units (174,574,175 and 161,233,046 units authorized; 170,951,457 and 157,437,608 units issued and outstanding at December 31, 2012 and 2011)	3,207	3,173
General partner interest	326	330
Accumulated other comprehensive loss	0	(5)
Total partners’ capital	3,533	3,498
Noncontrolling interest	77	33
Total partners’ capital and noncontrolling interest	3,610	3,531
TOTAL LIABILITIES AND PARTNERS’ CAPITAL AND NONCONTROLLING INTEREST	$ 6,157	$ 5,568