Quarterly Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2012

Quarterly Financial Data (Unaudited)

Quarterly Financial Data (Unaudited)

(13) Quarterly Financial Data (Unaudited)

        Unaudited summarized financial data by quarter for 2012 and 2011 is as follows (in thousands, except per share data):

	Year Ended December 31, 2012
	First Quarter			Second Quarter		Third Quarter		Fourth Quarter		Year
Operating revenues	$	921,173		$	937,214	$	865,259	$	810,726	$	3,534,372
Operating income		20,457			46,806		54,974		43,750		165,987
Net income (loss)		(682	)		16,960		20,933		13,946		51,157
Net income (loss) per common share:
Basic		(0.01	)		0.33		0.41		0.27		1.00
Diluted		(0.01	)		0.33		0.40		0.27		0.99
Weighted average common shares:
Basic:		50,881			50,944		51,241		51,296		51,090
Diluted:		50,881			51,789		52,153		52,161		51,746

	Year Ended December 31, 2011
	First Quarter			Second Quarter		Third Quarter		Fourth Quarter			Year
Operating revenues	$	865,951		$	933,697	$	955,425	$	899,850		$	3,654,923
Operating income		227			19,040		26,827		(4,989	)		41,105
Net income (loss)		(11,063	)		1,579		116		(17,967	)		(27,335	)
Net income (loss) per common share:
Basic		(0.21	)		0.03		0.00		(0.35	)		(0.52	)
Diluted		(0.21	)		0.03		0.00		(0.35	)		(0.52	)
Weighted average common shares:
Basic:		53,844			52,698		51,570		50,691			52,201
Diluted:		53,844			53,371		52,315		50,691			52,201