Note 5 - Employee Benefit Plans (Details) - Components of Net Periodic Benefit Cost for the Noncontributory Defined Benefit Pension Plan (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Components of Net Periodic Benefit Cost for the Noncontributory Defined Benefit Pension Plan [Abstract]
Service cost	$ 462	$ 620	$ 1,082	$ 1,240
Interest cost	940	1,033	1,972	2,065
Expected return on plan assets	(1,481)	(994)	(2,475)	(1,988)
Amortization of prior service cost		10	10	20
Recognized actuarial loss	1,539	1,032	2,521	1,863
Net periodic benefit cost	$ 1,460	$ 1,701	$ 3,110	$ 3,200