Note 6 - Stockholders' Equity (Details) - Repurchase of Equity Securities (USD $) In Thousands, except Share data, unless otherwise specified	1 Months Ended
	Sep. 30, 2014	Aug. 31, 2014	Jul. 31, 2014	Jun. 30, 2014	May 31, 2014	Apr. 30, 2014	Mar. 31, 2014	Feb. 28, 2014	Jan. 31, 2014
Repurchase of Equity Securities [Abstract]
Total Number of Common Shares Repurchased	186,654	77,700
Average Price Paid Per Common Share (in Dollars per share)	$ 35.48	$ 39.05
Total Number of Common Shares Purchased as Part of Publicly Announced Plans or Programs	637,973	451,319
Maximum Number (or Approximate Dollar Value) of Common Shares that May Yet Be Purchased Under the Plans or Programs (in Dollars)	$ 77,088	$ 83,711	$ 86,745	$ 86,745	$ 86,745	$ 86,745	$ 86,745	$ 86,745	$ 86,745