CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Transmission revenues	$ 86	$ 87
Equity earnings (Note 4)	42	31
Operation and maintenance expenses	(10)	(11)
Property taxes	(5)	(6)
General and administrative	(2)	(3)
Depreciation	(21)	(21)
Financial charges and other (Note 14)	(17)	(13)
Net income	73	64
Net income attributable to non-controlling interests		7
Net income attributable to controlling interests	73	57
Net income attributable to controlling interest allocation
General Partner	2	1
Net income attributable to controlling interests	73	57
Common units
Net income attributable to controlling interest allocation
Limited partners	$ 71	$ 56
Net income per common unit (Note 8) - basic (in dollars per unit)	$ 1.10	$ 0.88
Net income per common unit (Note 8) - diluted (in dollars per unit)	$ 1.10	$ 0.88
Weighted average common units outstanding - basic (in units)	64.4	63.6
Weighted average common units outstanding - diluted (in units)	64.4	63.6
Common units outstanding, end of period (in units)	64.7	63.6