Business Segment Information Business Segment Information (Tables)

6 Months Ended

Jun. 30, 2013

Segment Reporting Information, Additional Information [Abstract]

Schedule of Segment Reporting Information [Table Text Block]

Segment information and Corporate activities included in the accompanying Condensed Consolidated Statements of Income (Loss) were as follows (in thousands):

Three Months Ended June 30, 2013	External Operating Revenue		Intercompany Operating Revenue			Income (Loss) from Continuing Operations
Utilities:
Electric	$	154,338	$	3,694		$	10,610
Gas	105,836		—			3,192
Non-regulated Energy:
Power Generation	1,031		19,094			5,031
Coal Mining	6,807		7,511			1,973
Oil and Gas	11,814		—			(1,964		)
Corporate activities (a)	—		—			11,679
Intercompany eliminations	—		(30,299		)	(3		)
Total	$	279,826	$	—		$	30,518

Three Months Ended June 30, 2012	External Operating Revenue		Intercompany Operating Revenue			Income (Loss) from Continuing Operations
Utilities:
Electric	$	144,560	$	5,174		$	14,159
Gas	70,386		—			1,159
Non-regulated Energy:
Power Generation	759		17,975			3,926
Coal Mining	6,037		7,090			1,234
Oil and Gas (b)	20,621		—			(19,621		)
Corporate activities (a)	—		—			(13,180		)
Intercompany eliminations	—		(30,239		)	—
Total	$	242,363	$	—		$	(12,323	)

Six Months Ended June 30, 2013	External Operating Revenues		Intercompany Operating Revenues			Income (Loss) from Continuing Operations
Utilities:
Electric	$	312,821	$	7,841		$	22,966
Gas	305,648		—			21,675
Non-regulated Energy:
Power Generation	2,053		38,432			10,675
Coal Mining	12,817		15,084			3,038
Oil and Gas	27,158		—			(2,017		)
Corporate (a)	—		—			17,378
Intercompany eliminations	—		(61,357		)	—
Total	$	660,497	$	—		$	73,715

Six Months Ended June 30, 2012	External Operating Revenues		Intercompany Operating Revenues			Income (Loss) from Continuing Operations
Utilities:
Electric	$	300,693	$	8,210		$	22,905
Gas	250,908		—			16,366
Non-regulated Energy:
Power Generation	1,937		36,424			10,840
Coal Mining	12,410		15,706			2,234
Oil and Gas(b)	42,266		—			(19,608		)
Corporate (a)(c)	—		—			(9,789		)
Intercompany eliminations	—		(60,340		)	—
Total	$	608,214	$	—		$	22,948

__________

(a) Income (loss) from continuing operations includes a $12.2 million and a $17.1 million net after-tax non-cash mark-to-market gain on certain interest rate swaps for the three and six months ended June 30, 2013, respectively, and a $10.1 million and a $2.3 million net after-tax non-cash mark-to-market loss for the three and six months ended June 30, 2012, respectively, for those same interest rate swaps.

(b) Income (loss) from continuing operations includes a $17.3 million non-cash after-tax ceiling test impairment charge. See Note 14 for further information.

(c) Certain indirect corporate costs and inter-segment interest expense after-tax totaling $1.6 million for the six months ended June 30, 2012, were included in the Corporate activities in continuing operations and were not reclassified as discontinued operations.

Segment information and Corporate balances included in the accompanying Condensed Consolidated Balance Sheets were as follows (in thousands):

Total Assets (net of inter-company eliminations) as of:	June 30, 2013		Dec. 31, 2012		June 30, 2012
Utilities:
Electric (a)	$	2,417,952	$	2,387,458	$	2,300,948
Gas	734,337		765,165		684,545
Non-regulated Energy:
Power Generation (a)	108,515		119,170		122,856
Coal Mining	82,553		83,810		90,021
Oil and Gas	256,855		258,460		416,617
Corporate activities	146,302		115,408		159,293
Total assets	$	3,746,514	$	3,729,471	$	3,774,280

__________

(a) The PPA pertaining to the portion of the Pueblo Airport Generation Station owned by Colorado IPP that supports Colorado customers is accounted for as a capital lease. Therefore, assets owned by the Power Generation segment are included in Total assets of Electric Utilities Segment under this accounting for a capital lease.