CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash Generated From Operations
Net income	$ 127	$ 108
Depreciation	43	42
Amortization of debt issue costs reported as interest expense (Note 3)	1	1
Equity allowance for funds used during construction		(1)
Change in operating working capital (Note 10)	3	1
Total cash generated from operations	170	151
Investing Activities
Acquisition of the remaining 30 percent interest in GTN		(264)
Capital expenditures	(18)	(12)
Other	2	(1)
Total investing activities	(171)	(258)
Financing Activities
Distributions paid to non-controlling interests		(9)
Common unit issuance, net		26
Common unit issuance subject to rescission, net (Note 7)	83
Equity contribution by the General Partner		2
Long-term debt issued, net of discount (Note 5)	205	424
Long-term debt repaid (Note 5)	(155)	(205)
Debt issuance costs		(3)
Total financing activities	2	125
Increase in cash and cash equivalents	1	18
Cash and cash equivalents, beginning of period	39	26
Cash and cash equivalents, end of period	40	44
Class B units
Financing Activities
Distributions paid (Note 7)	(12)
Common units and General Partner interest combined
Financing Activities
Distributions paid (Note 9)	(119)	(110)
Northern Border
Investing Activities
Cumulative distributions in excess of equity earnings	25	13
Great Lakes
Investing Activities
Cumulative distributions in excess of equity earnings	17	10
Investment in Great Lakes / Acquisition of PNGTS (Note 6)	(4)	$ (4)
Portland Natural Gas Transmission System
Cash Generated From Operations
Equity earnings in excess of cumulative distributions	(4)
Investing Activities
Investment in Great Lakes / Acquisition of PNGTS (Note 6)	$ (193)