UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities
Net income	$ 73.0	$ 68.0
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation, amortization and accretion	6.2	5.9
Non-cash interest expense	0.0	0.1
Undistributed equity earnings	(0.8)	(1.0)
Changes in operating assets and liabilities
Accounts receivable	2.7	0.3
Allowance oil	1.1	(0.4)
Prepaid expenses	(0.5)	1.6
Accounts payable	(0.1)	(0.2)
Deferred revenue	8.5	(1.8)
Accrued liabilities	3.4	(0.1)
Net cash provided by operating activities	93.5	72.4
Cash flows from investing activities
Capital expenditures	(7.3)	(4.7)
Purchase price adjustment	0.4	0.0
Return of investment	6.0	4.1
Net cash used in investing activities	(0.9)	(0.6)
Cash flows from financing activities
Net proceeds from public offerings	0.0	420.4
Contributions from general partner	0.0	8.7
Repayment of credit facilities	0.0	(410.0)
Distributions to noncontrolling interest	(3.2)	(12.4)
Distributions to unitholders and general partner	(58.6)	(35.3)
Other contribution from parent	2.8	1.8
Capital lease payments	(0.2)	0.0
Credit facilities issuance costs	(0.7)	0.0
Net cash used in financing activities	(59.9)	(26.8)
Net increase in cash and cash equivalents	32.7	45.0
Cash and cash equivalents at beginning of the period	121.9	93.0
Cash and cash equivalents at end of the period	154.6	138.0
Non-cash investing and financing transactions
Change in accrued capital expenditures	4.7	0.4
Other non-cash contributions from Parent	$ 3.8	$ 0.1