Note 5 - Derivative Instruments (Tables)

3 Months Ended

Mar. 31, 2014

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]

In Bcf (1)	March 31, 2014 (2)			December 31, 2013			March 31, 2013
Hedge designation
Cash flow hedges		6			6			6
Not designated as hedges		277			183			304
Total hedges		283			189			310
Hedge position
Short position		(2,491	)		(2,622	)		(1,902	)
Long position		2,774			2,811			2,212
Net long position		283			189			310

Loss Recognized In Income [Table Text Block]

	Three months ended March 31,
In millions	2014		2013
Nicor Gas	$	2	$	(1	)
Elizabethtown Gas		3		(3	)

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]

		March 31, 2014						December 31, 2013						March 31, 2013
In millions	Classification	Assets			Liabilities			Assets			Liabilities			Assets			Liabilities
Designated as cash flow hedges and fair value hedges
Natural gas contracts	Current	$	2		$	-		$	3		$	(1	)	$	3		$	(1	)
Interest rate swap agreements	Current		-			-			-			-			5			-
Total			2			-			3			(1	)		8			(1	)
Not designated as cash flow hedges
Natural gas contracts	Current		675			(703	)		691			(761	)		332			(327	)
Natural gas contracts	Long-term		80			(98	)		206			(220	)		46			(48	)
Total			755			(801	)		897			(981	)		378			(375	)
Gross amount of recognized assets and liabilities (1)			757			(801	)		900			(982	)		386			(376	)
Gross amounts offset in our unaudited Condensed Consolidated Statements of Financial Position (2)			(619	)		719			(781	)		902			(275	)		352
Net amounts of assets and liabilities presented in our unaudited Condensed Consolidated Statements of Financial Position (3)		$	138		$	(82	)	$	119		$	(80	)	$	111		$	(24	)

Schedule of Derivative Instruments [Table Text Block]

	Three months ended March 31,
In millions	2014			2013
Designated as cash flow hedges
Natural gas contracts - net gain reclassified from OCI to cost of goods sold	$	3		$	-
Natural gas contracts - net gain reclassified from OCI to operation and maintenance expense		1			-
Interest rate swaps - loss reclassified from OCI to interest expense		-			(3	)
Income tax benefit		-			1
Net of tax		4			(2	)
Not designated as hedges (1)
Natural gas contracts - net fair value adjustments recorded in operating revenues		(30	)		(24	)
Natural gas contracts - net fair value adjustments recorded in cost of goods sold (2)		2			-
Income tax benefit		11			8
Net of tax		(17	)		(16	)
Total losses on derivative instruments, net of tax	$	(13	)	$	(18	)