CONSOLIDATED STATEMENT OF INCOME (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Equity earnings from unconsolidated affiliates (Note 3)	$ 153.5	[1]	$ 126.0	[1]	$ 99.4	[1]
Transmission revenues	70.4		69.1		67.9
Operating expenses	(14.6)		(13.0)		(11.0)
General and administrative	(8.7)		(4.4)		(6.2)
Depreciation	(15.2)		(15.0)		(14.7)
Financial charges and other (Note 8)	(28.0)		(25.6)		(29.3)
Net income	157.4	[1],[2]	137.1	[2]	106.1	[2],[3]
Net income allocation (Note 9)
Common units	154.3		134.4		90.6
General partner	3.1		2.7		7.2
Net income allocated to partners	$ 157.4		$ 137.1		$ 97.8
Net income per common unit (Note 9) (in dollars per unit)	$ 3.02		$ 2.91		$ 2.34
Weighted average common units outstanding (millions) (in units)	51.1		46.2		38.7
Common units outstanding, end of year (millions) (in units)	53.5		46.2		46.2

[1] Includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.

[2] Recast as discussed in Notes 2 and 5 and includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.

[3] Recast as discussed in Notes 2 and 5.