Note 4 - Fair Value Measurements (Detail) - Asset Allocation of Retirement Plan (USD $) In Millions, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011
Cash [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	$ 14	[1]	$ 13	[1]
Cash [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	2	[1]	0	[1]
Cash [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[1]	0	[1]
Cash [Member] | Pension Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	16	[1]	13	[1]
Cash [Member] | Pension Plans, Defined Benefit [Member]
Percent of Total	2.00%	[1]	2.00%	[1]
Cash [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	1		1
Cash [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	0		0
Cash [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0		0
Cash [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	1		1
Cash [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Percent of Total	1.00%		2.00%
U.S. Large Cap [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	69	[1],[2]	95	[1],[2]
U.S. Large Cap [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	181	[1],[2]	134	[1],[2]
U.S. Large Cap [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[1],[2]	0	[1],[2]
U.S. Large Cap [Member] | Pension Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	250	[1],[2]	229	[1],[2]
U.S. Large Cap [Member] | Pension Plans, Defined Benefit [Member]
Percent of Total	30.00%	[1],[2]	30.00%	[1],[2]
U.S. Large Cap [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[2]	0	[2]
U.S. Large Cap [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	38	[2]	34	[2]
U.S. Large Cap [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[2]	0	[2]
U.S. Large Cap [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	38	[2]	34	[2]
U.S. Large Cap [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Percent of Total	55.00%	[2]	56.00%	[2]
U.S. Small Cap [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	60	[1],[2]	53	[1],[2]
U.S. Small Cap [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	22	[1],[2]	25	[1],[2]
U.S. Small Cap [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[1],[2]	0	[1],[2]
U.S. Small Cap [Member] | Pension Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	82	[1],[2]	78	[1],[2]
U.S. Small Cap [Member] | Pension Plans, Defined Benefit [Member]
Percent of Total	10.00%	[1],[2]	10.00%	[1],[2]
U.S. Small Cap [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[2]	0	[2]
U.S. Small Cap [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	0	[2]	0	[2]
U.S. Small Cap [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[2]	0	[2]
U.S. Small Cap [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	0	[2]	0	[2]
U.S. Small Cap [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Percent of Total	0.00%	[2]	0.00%	[2]
International Companies [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[1],[3]	0	[1],[3]
International Companies [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	120	[1],[3]	107	[1],[3]
International Companies [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[1],[3]	0	[1],[3]
International Companies [Member] | Pension Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	120	[1],[3]	107	[1],[3]
International Companies [Member] | Pension Plans, Defined Benefit [Member]
Percent of Total	14.00%	[1],[3]	14.00%	[1],[3]
International Companies [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[3]	0	[3]
International Companies [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	12	[3]	10	[3]
International Companies [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[3]	0	[3]
International Companies [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	12	[3]	10	[3]
International Companies [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Percent of Total	18.00%	[3]	16.00%	[3]
Emerging Markets [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[1],[4]	0	[1],[4]
Emerging Markets [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	34	[1],[4]	25	[1],[4]
Emerging Markets [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[1],[4]	0	[1],[4]
Emerging Markets [Member] | Pension Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	34	[1],[4]	25	[1],[4]
Emerging Markets [Member] | Pension Plans, Defined Benefit [Member]
Percent of Total	4.00%	[1],[4]	3.00%	[1],[4]
Emerging Markets [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[4]	0	[4]
Emerging Markets [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	0	[4]	0	[4]
Emerging Markets [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[4]	0	[4]
Emerging Markets [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	0	[4]	0	[4]
Emerging Markets [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Percent of Total	0.00%	[4]	0.00%	[4]
Corporate Bonds [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[1],[5]	0	[1],[5]
Corporate Bonds [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	216	[1],[5]	191	[1],[5]
Corporate Bonds [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[1],[5]	0	[1],[5]
Corporate Bonds [Member] | Pension Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	216	[1],[5]	191	[1],[5]
Corporate Bonds [Member] | Pension Plans, Defined Benefit [Member]
Percent of Total	26.00%	[1],[5]	25.00%	[1],[5]
Corporate Bonds [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[5]	0	[5]
Corporate Bonds [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	18	[5]	0	[5]
Corporate Bonds [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[5]	0	[5]
Corporate Bonds [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	18	[5]	0	[5]
Corporate Bonds [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Percent of Total	26.00%	[5]	0.00%	[5]
Other Investments Or Government Muni Bonds [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[1]	0	[1]
Other Investments Or Government Muni Bonds [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	30	[1]	28	[1]
Other Investments Or Government Muni Bonds [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[1]	0	[1]
Other Investments Or Government Muni Bonds [Member] | Pension Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	30	[1]	28	[1]
Other Investments Or Government Muni Bonds [Member] | Pension Plans, Defined Benefit [Member]
Percent of Total	3.00%	[1]	4.00%	[1]
Other Investments Or Government Muni Bonds [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0		0
Other Investments Or Government Muni Bonds [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	0		16
Other Investments Or Government Muni Bonds [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0		0
Other Investments Or Government Muni Bonds [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	0		16
Other Investments Or Government Muni Bonds [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Percent of Total	0.00%		26.00%
Global Hedged Equity [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[1],[6]	0	[1],[6]
Global Hedged Equity [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	0	[1],[6]	0	[1],[6]
Global Hedged Equity [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	38	[1],[6]	30	[1],[6]
Global Hedged Equity [Member] | Pension Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	38	[1],[6]	30	[1],[6]
Global Hedged Equity [Member] | Pension Plans, Defined Benefit [Member]
Percent of Total	4.00%	[1],[6]	4.00%	[1],[6]
Global Hedged Equity [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[6]	0	[6]
Global Hedged Equity [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	0	[6]	0	[6]
Global Hedged Equity [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[6]	0	[6]
Global Hedged Equity [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	0	[6]	0	[6]
Global Hedged Equity [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Percent of Total	0.00%	[6]	0.00%	[6]
Absolute Return [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[1],[7]	0	[1],[7]
Absolute Return [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	0	[1],[7]	0	[1],[7]
Absolute Return [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	36	[1],[7]	34	[1],[7]
Absolute Return [Member] | Pension Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	36	[1],[7]	34	[1],[7]
Absolute Return [Member] | Pension Plans, Defined Benefit [Member]
Percent of Total	4.00%	[1],[7]	5.00%	[1],[7]
Absolute Return [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[7]	0	[7]
Absolute Return [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	0	[7]	0	[7]
Absolute Return [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[7]	0	[7]
Absolute Return [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	0	[7]	0	[7]
Absolute Return [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Percent of Total	0.00%	[7]	0.00%	[7]
Private Capital [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[1],[8]	0	[1],[8]
Private Capital [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	0	[1],[8]	0	[1],[8]
Private Capital [Member] | Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	23	[1],[8]	25	[1],[8]
Private Capital [Member] | Pension Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	23	[1],[8]	25	[1],[8]
Private Capital [Member] | Pension Plans, Defined Benefit [Member]
Percent of Total	3.00%	[1],[8]	3.00%	[1],[8]
Private Capital [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	0	[8]	0	[8]
Private Capital [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	0	[8]	0	[8]
Private Capital [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0	[8]	0	[8]
Private Capital [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	0	[8]	0	[8]
Private Capital [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Percent of Total	0.00%	[8]	0.00%	[8]
Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	143	[1]	161	[1]
% of fair value hierarchy	17.00%	[1]	21.00%	[1]
Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	605	[1]	510	[1]
% of fair value hierarchy	72.00%	[1]	67.00%	[1]
Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	97	[1]	89	[1]
% of fair value hierarchy	11.00%	[1]	12.00%	[1]
Pension Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	845	[1]	760	[1]
% of fair value hierarchy	100.00%	[1]	100.00%	[1]
Pension Plans, Defined Benefit [Member]
Percent of Total	100.00%	[1]	100.00%	[1]
Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value of Plan Assets	1		1
% of fair value hierarchy	1.00%		2.00%
Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Plan Assets	68		60
% of fair value hierarchy	99.00%		98.00%
Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Plan Assets	0		0
% of fair value hierarchy	0.00%		0.00%
Other Postretirement Benefit Plans, Defined Benefit [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value of Plan Assets	$ 69		$ 61
% of fair value hierarchy	100.00%		100.00%
Other Postretirement Benefit Plans, Defined Benefit [Member]
Percent of Total	100.00%		100.00%

[1] Includes $8 million at December 31, 2012 and $6 million at December 31, 2011 of medical benefit (health and welfare) component for 401h accounts to fund a portion of the other retirement benefits.

[2] Includes funds that invest primarily in United States common stocks.

[3] Includes funds that invest primarily in foreign equity and equity-related securities.

[4] Includes funds that invest primarily in common stocks of emerging markets.

[5] Includes funds that invest primarily in investment grade debt and fixed income securities.

[6] Includes funds that invest in limited / general partnerships, managed accounts, and other investment entities issued by non-traditional firms or "hedge funds."

[7] Includes funds that invest primarily in investment vehicles and commodity pools as a "fund of funds."

[8] Includes funds that invest in private equity and small buyout funds, partnership investments, direct investments, secondary investments, directly / indirectly in real estate and may invest in equity securities of real estate related companies, real estate mortgage loans, and real-estate mezzanine loans.