Note 8 - Stock-Based Compensation (Details) - Phantom Stock Plan (Phantom Share Units (PSUs) [Member], USD $)	6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013
Phantom Share Units (PSUs) [Member]
Note 8 - Stock-Based Compensation (Details) - Phantom Stock Plan [Line Items]
Granted	8,609
Granted	$ 19.89
Forfeited	(13)
Forfeited	$ 21.51
Distributions	(668)
Distributions	$ 20.10
Shares	67,251	59,323
Fair Value	$ 20.55	$ 20.70
Vested at June 30, 2014	67,066
Vested at June 30, 2014	$ 20.55