Note 12 - Summary of Stock-Settled Stock Appreciation Rights Transactions (Details) - Stock Appreciation Rights (SARs) [Member] - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Outstanding (in shares)	522,024	452,812
Outstanding (in dollars per share)	$ 6.17	$ 5.76
Granted (in shares)	53,292	137,382
Granted (in dollars per share)	$ 18.66	$ 7.36
Exercised (in shares)	(193,750)	(68,170)
Exercised (in dollars per share)	$ 5.73	$ 5.85
Outstanding (in shares)	381,566	522,024
Outstanding (in dollars per share)	$ 8.14	$ 6.17