Note 7 - Shareholders' Equity (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Stock Repurchase Program, Authorized Amount (in Dollars)	$ 100,000,000
Treasury Stock, Shares, Acquired (in Shares)	782,000	264,000
Treasury Stock, Value, Acquired, Cost Method	35,900,000	12,455,000	6,621,000
Shares Paid for Tax Withholding for Share Based Compensation (in Shares)	80,000	92,000
Adjustments Related to Tax Withholding for Share-based Compensation	$ 3,800,000	$ 4,300,000