CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Project revenue:
Revenues	$ 66.2	$ 124.0	$ 146.2	$ 222.4
Project expenses:
Fuel	15.0	24.0	37.2	52.9
Operations and maintenance	27.2	23.3	48.5	43.6
Depreciation and amortization	21.0	29.5	44.7	59.0
Total project costs	63.2	76.8	130.4	155.5
Project other income (loss):
Change in fair value of derivative instruments (Notes 7 and 8)	(0.2)	(2.7)	3.5	(3.9)
Equity in earnings (loss) of unconsolidated affiliates (Note 4)	11.2	(54.4)	23.5	(45.4)
Interest, net	(0.4)	(2.2)	(1.0)	(4.4)
Total project other income	10.6	(59.3)	26.0	(53.7)
Project income (loss)	13.6	(12.1)	41.8	13.2
Administrative and other expenses:
Administration	6.2	5.7	12.2	12.1
Interest expense, net	11.1	18.4	26.1	35.7
Foreign exchange (gain) loss	(5.4)	5.9	(13.6)	8.3
Other income, net (Note 8)	(0.2)		(2.2)
Total administrative and other expenses	11.7	30.0	22.5	56.1
Income (loss) from operations before income taxes	1.9	(42.1)	19.3	(42.9)
Income tax expense (benefit) (Note 9)	0.9	(22.3)	4.2	(22.6)
Net income (loss)	1.0	(19.8)	15.1	(20.3)
Net income (loss) attributable to preferred shares of a subsidiary company (Note 12)	1.6	2.1	(0.1)	4.3
Net (loss) income attributable to Atlantic Power Corporation	$ (0.6)	$ (21.9)	$ 15.2	$ (24.6)
Net (loss) income per share attributable to Atlantic Power Corporation shareholders: (Note 11)
Basic	$ (0.01)	$ (0.19)	$ 0.13	$ (0.21)
Diluted	$ (0.01)	$ (0.19)	$ 0.13	$ (0.21)
Weighted average number of common shares outstanding: (Note 11)
Basic (in shares)	112.4	115.2	113.6	115.0
Diluted (in shares)	112.4	115.2	140.1	115.0
Energy sales
Project revenue:
Revenues	$ 31.4	$ 40.0	$ 69.8	$ 77.1
Energy capacity revenue
Project revenue:
Revenues	23.3	28.3	43.4	47.8
Other
Project revenue:
Revenues	$ 11.5	$ 55.7	$ 33.0	$ 97.5