Note 6 - Available-for-Sale Investments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			12 Months Ended
	Mar. 31, 2015		Mar. 31, 2014	Dec. 31, 2014
Available For Sale Investments [Abstract]
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	$ 37	[1]
Marketable Securities, Realized Loss, Other than Temporary Impairments, Amount	4			4
Proceeds from Sale of Short-term Investments	$ 282		$ 338

[1] Includes $37 million of asset-based securities that mature over time and are being reported at their final maturity dates.