Note 13 - Asset Retirement Obligation (Tables)

12 Months Ended

Dec. 31, 2014

Asset Retirement Obligation Disclosure [Abstract]

Schedule of Asset Retirement Obligations [Table Text Block]

	Year Ended December 31,
	2014			2013
	(Dollars in thousands)
Balance at beginning of year	$	18,679		$	19,289
Revision in estimated cash flows		(1,395	)		(2,742	)
Liabilities incurred		356			588
Accretion expense		1,502			1,544
Balance at end of year	$	19,142		$	18,679