Summarized Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2011

Quarterly Financial Data [Line Items]

Schedule of quarterly operating results

The Company's business is seasonal in character. The following data summarizes quarterly operating results.

	Year ended December 31, 2011
(in thousands, except per share amounts)	First		Second		Third		Fourth*
Operating revenues	$	486,364	$	330,399	$	378,568	$	288,148
Operating income	$	159,881	$	106,335	$	150,412	$	31,641
Net income	$	94,268	$	63,325	$	87,599	$	14,432
Diluted earnings per average common share	$	1.30	$	0.87	$	1.21	$	0.20
Basic earnings per average common share	$	1.31	$	0.88	$	1.22	$	0.20

*The three months ended December 31, 2011 includes an after-tax non-cash mark-to-market loss on derivatives of $56.6 million, or $0.78 per diluted share.

	Year ended December 31, 2010
(in thousands, except per share amounts)	First		Second		Third		Fourth
Operating revenues	$	574,914	$	333,725	$	295,804	$	374,091
Operating income	$	192,198	$	98,293	$	67,320	$	135,566
Net income	$	116,710	$	55,543	$	38,304	$	80,250
Diluted earnings per average common share	$	1.62	$	0.77	$	0.53	$	1.11
Basic earnings per average common share	$	1.63	$	0.77	$	0.53	$	1.12

Alabama Gas Corporation

Quarterly Financial Data [Line Items]

Schedule of quarterly operating results

Alagasco's business is seasonal in character and influenced by weather conditions. The following data summarizes Alagasco's quarterly operating results.

	Year ended December 31, 2011
(in thousands)	First		Second		Third			Fourth
Operating revenues	$	269,572	$	86,309	$	59,616		$	119,456
Operating income (loss)	$	75,059	$	1,163	$	(10,681	)	$	20,675
Net income (loss)	$	44,175	$	262	$	(9,093	)	$	11,258

	Year ended December 31, 2010
(in thousands)	First		Second			Third			Fourth
Operating revenues	$	337,300	$	99,139		$	61,693		$	121,640
Operating income (loss)	$	75,255	$	3,138		$	(9,015	)	$	19,005
Net income (loss)	$	44,246	$	(340	)	$	(7,120	)	$	10,097