Note 9 - Pension and Other Postretirement Benefit Plans (Detail) (USD $)	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Employee Pension Plan [Member]
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year		$ 800,000
Defined Benefit Plan, Contributions by Employer	159,000
Outside Director Pension Plan [Member]
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year		200,000
Defined Benefit Plan, Contributions by Employer	22,000
Other Postretirement Benefit Plans [Member]
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year		200,000
Defined Benefit Plan, Contributions by Employer	$ 13,000