Note 4 - Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2014

Note 4 - Fair Value Measurements (Tables) [Line Items]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

In millions	2014		2013
Long-term debt carrying amount	$	3,802	$	3,813
Long-term debt fair value (1)		4,231		3,956

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

	Fair value measurements using significant unobservable inputs - Level 3 (1)
In millions	Global hedged equity			Absolute return		Private capital			Total
Balance at December 31, 2012	$	38		$	36	$	23		$	97
Actual return on plan assets		5			3		4			12
Sales		-			-		(5	)		(5	)
Balance at December 31, 2013	$	43		$	39	$	22		$	104
Actual return on plan assets		1			3		2			6
Sales		(15	)		-		(4	)		(19	)
Balance at December 31, 2014	$	29		$	42	$	20		$	91
(1)There were no transfers out of Level 3, or between Level 1 and Level 2 for any of the periods presented.

Natural Gas and Interest Rate Derivatives [Member]

Note 4 - Fair Value Measurements (Tables) [Line Items]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	2014					2013
In millions	Assets (1)		Liabilities			Assets (1)		Liabilities
Natural gas derivatives
Quoted prices in active markets (Level 1)	$	58	$	(80	)	$	6	$	(79	)
Significant other observable inputs (Level 2)		174		(94	)		67		(79	)
Netting of cash collateral		52		81			43		78
Total carrying value (2) (3)	$	284	$	(93	)	$	116	$	(80	)

Natural Gas Derivatives [Member]

Note 4 - Fair Value Measurements (Tables) [Line Items]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	December 31, 2014
	Pension plans (1)															Welfare plans
In millions	Level 1			Level 2			Level 3			Total			% of total			Level 1			Level 2			Level 3			Total			% of total
Cash	$	4		$	1		$	-		$	5			1	%	$	1		$	-		$	-		$	1			1	%
Equity securities:
U.S. large cap (2)	$	95		$	203		$	-		$	298			33	%	$	-		$	51		$	-		$	51			57	%
U.S. small cap (2)		76			24			-			100			11	%		-			-			-			-			-	%
International companies (3)		-			123			-			123			13	%		-			16			-			16			18	%
Emerging markets (4)		-			31			-			31			3	%		-			-			-			-			-	%
Total equity securities	$	171		$	381		$	-		$	552			60	%	$	-		$	67		$	-		$	67			75	%
Fixed income securities:
Corporate bonds (5)	$	-		$	233		$	-		$	233			25	%	$	-		$	22		$	-		$	22			24	%
Other (or gov’t/muni bonds)		-			33			-			33			4	%		-			-			-			-			-	%
Total fixed income securities	$	-		$	266		$	-		$	266			29	%	$	-		$	22		$	-		$	22			24	%
Other types of investments:
Global hedged equity (6)	$	-		$	-		$	29		$	29			3	%	$	-		$	-		$	-		$	-			-	%
Absolute return (7)		-			-			42			42			5	%		-			-			-			-			-	%
Private capital (8)		-			-			20			20			2	%		-			-			-			-			-	%
Total other investments	$	-		$	-		$	91		$	91			10	%	$	-		$	-		$	-		$	-			-	%
Total assets at fair value	$	175		$	648		$	91		$	914			100	%	$	1		$	89		$	-		$	90			100	%
% of fair value hierarchy		19	%		71	%		10	%		100	%					1	%		99	%		-	%		100	%

	December 31, 2013
	Pension plans (1)															Welfare plans
In millions	Level 1			Level 2			Level 3			Total			% of total			Level 1			Level 2			Level 3			Total			% of total
Cash	$	3		$	1		$	-		$	4			-	%	$	1		$	-		$	-		$	1			1	%
Equity securities:
U.S. large cap (2)	$	93		$	205		$	-		$	298			33	%	$	-		$	52		$	-		$	52			62	%
U.S. small cap (2)		72			29			-			101			11	%		-			-			-			-			-	%
International companies (3)		-			139			-			139			15	%		-			14			-			14			17	%
Emerging markets (4)		-			34			-			34			4	%		-			-			-			-			-	%
Total equity securities	$	165		$	407		$	-		$	572			63	%	$	-		$	66		$	-		$	66			79	%
Fixed income securities:
Corporate bonds (5)	$	-		$	207		$	-		$	207			23	%	$	-		$	17		$	-		$	17			20	%
Other (or gov’t/muni bonds)		-			29			-			29			3	%		-			-			-			-			-	%
Total fixed income securities	$	-		$	236		$	-		$	236			26	%	$	-		$	17		$	-		$	17			20	%
Other types of investments:
Global hedged equity (6)	$	-		$	-		$	43		$	43			5	%	$	-		$	-		$	-		$	-			-	%
Absolute return (7)		-			-			39			39			4	%		-			-			-			-			-	%
Private capital (8)		-			-			22			22			2	%		-			-			-			-			-	%
Total other investments	$	-		$	-		$	104		$	104			11	%	$	-		$	-		$	-		$	-			-	%
Total assets at fair value	$	168		$	644		$	104		$	916			100	%	$	1		$	83		$	-		$	84			100	%
% of fair value hierarchy		19	%		70	%		11	%		100	%					1	%		99	%		-	%		100	%