UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities
Net income	$ 137.0	$ 65.0
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation, amortization and accretion	12.0	11.0
Loss from revision of asset retirement obligation	2.0	0.0
Undistributed equity earnings	(3.0)	(1.0)
Changes in operating assets and liabilities
Accounts receivable	5.0	13.0
Allowance oil	2.0	0.0
Prepaid expenses and other assets	4.0	3.0
Accounts payable	(1.0)	5.0
Deferred revenue and other unearned income	(8.0)	(2.0)
Accrued liabilities	0.0	15.0
Net cash provided by operating activities	150.0	109.0
Cash flows from investing activities
Capital expenditures	(10.0)	(9.0)
Contributions to investment	(5.0)	0.0
Return of investment	8.0	11.0
Net cash (used in) provided by investing activities	(7.0)	2.0
Cash flows from financing activities
Net proceeds from equity offerings	0.0	973.0
Repayments of credit facilities	0.0	(973.0)
Contributions from general partner	0.0	20.0
Distributions to noncontrolling interests	(3.0)	(2.0)
Distributions to unitholders and general partner	(129.0)	(83.0)
Other contributions from Parent	7.0	1.0
Net cash used in financing activities	(125.0)	(64.0)
Net increase in cash and cash equivalents	18.0	47.0
Cash and cash equivalents at beginning of the period	208.0	138.0
Cash and cash equivalents at end of the period	226.0	185.0
Non-cash investing and financing transactions:
Change in accrued capital expenditures	2.0	5.0
Other contributions from Parent	$ 0.0	$ 4.0