Note 5 - Marketable Securities, Available-for-sale (Tables)

12 Months Ended

Dec. 31, 2015

Disclosure Text Block Supplement [Abstract]

Schedule of Available-for-sale Securities Reconciliation [Table Text Block]

	December 31, 2015
	Amortized Cost		Gross Unrealized Gains		Estimated Fair Value
	(Dollars in thousands)
Type of security:
Municipal bond and metropolitan district securities	$	19,439	$	5	$	19,444

Available-for-sale Securities [Table Text Block]

	December 31, 2015
	(Dollars in thousands)
Contractual maturity:
Maturing in one year or less	$	-
Maturing after three years		19,444
Total marketable securities, available-for-sale	$	19,444