Note 7 - Earnings Per Share ("EPS") (Details Textual) - USD ($)				3 Months Ended
	Mar. 31, 2016	Feb. 29, 2016	Feb. 26, 2016	Mar. 31, 2016	Mar. 31, 2015
Accelerated Stock Repurchase [Member] | Morgan Stanley & Co., LLC [Member] | Common Stock [Member]
Stock Repurchase Program, Authorized Amount			$ 25
Accelerated Share Repurchases, Initial Price Paid Per Share		$ 46.40
Stock Repurchase Program, Percentage Repurchased		70.00%
Accelerated Stock Repurchase [Member] | Morgan Stanley & Co., LLC [Member] | Additional Paid-in Capital [Member]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 7,500,000			$ 7,500,000
Accelerated Stock Repurchase [Member] | Morgan Stanley & Co., LLC [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0.2
Payments for Repurchase of Common Stock			$ 25,000,000
Stock Repurchased and Retired During Period, Shares		377,155
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount				300,000	100,000
Payments for Repurchase of Common Stock				$ 25,000,000