CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Millions	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
OPERATING ACTIVITIES:
Net income	$ 98.2	$ 144.7
Adjustments to reconcile to cash provided by operations:
Depreciation and amortization	113.1	107.1
Amortization of deferred costs	5.1	4.6
Asset impairment	28.5	2.5
Loss on debt extinguishment	7.4	0
Storage gas loss	3.7	0
Net loss on disposal of operating assets	1.4	1.1
Changes in operating assets and liabilities:
Trade and other receivables	4.8	22.3
Gas receivables and storage assets	(3.8)	(12.9)
Costs recoverable from customers	(2.5)	(2.7)
Other assets	(7.6)	(1.8)
Trade and other payables	(2.8)	(14.5)
Other payables, affiliates	(0.7)	2.4
Gas payables	(1.4)	10.0
Accrued liabilities	10.2	1.8
Other liabilities	(10.9)	(13.1)
Net cash provided by operating activities	242.7	251.5
INVESTING ACTIVITIES:
Capital expenditures	(73.7)	(130.5)
Proceeds from sale of operating assets	5.7	0
Advances to affiliate	0	(0.2)
Net cash used in investing activities	(68.0)	(130.7)
FINANCING ACTIVITIES:
Proceeds from long-term debt, net of issuance costs	437.6	0
Repayment of borrowings from long-term debt	(135.0)	0
Payments of premiums on extinguishment of long-term debt	(11.8)	0
Proceeds from borrowings on revolving credit agreement	265.0	125.0
Repayment of borrowings on revolving credit agreement	(700.0)	0
Payments on note payable	0	(0.3)
Payments associated with registration rights agreement	0	(10.7)
Advances from affiliate	0	(0.1)
Distributions paid	(205.2)	(196.8)
Proceeds from sale of common units	170.0	0
Capital contribution from general partner	3.6	0
Net cash used in financing activities	(175.8)	(82.9)
(Decrease) increase in cash and cash equivalents	(1.1)	37.9
Cash and cash equivalents at beginning of period	55.0	45.8
Cash and Cash Equivalents at End of Period	$ 53.9	$ 83.7