Note 7 - Stock-Based Compensation (Detail) - Nonvested Performance Based Units (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Accrued	$ 3	$ 4
Maximum aggregate payout	$ 16	$ 11

maximum payout on performance share unit awards as awarded by a company to their employees as a form of incentive compensation.

No definition available.

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